Systems and methods for treating hollow anatomical structures

ABSTRACT

An apparatus for treating a hollow anatomical structure can include a light delivery device. The light delivery device comprises an optical fiber that is located in a lumen of a shaft suitable for insertion into the hollow anatomical structure and has a fiber tip located proximal of a distal end of the shaft during treatment of the hollow anatomical structure. The apparatus can further include a liquid source for providing a liquid flow over the optical fiber at a predetermined liquid flow rate.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit under 35 U.S.C. §119(e) of U.S.Provisional Applications No. 60/914,660, filed Apr. 27, 2007, titledSYSTEMS AND METHODS FOR TREATING HOLLOW ANATOMICAL STRUCTURES; and No.60/986,577, filed Nov. 8, 2007, titled SYSTEMS AND METHODS FOR TREATINGHOLLOW ANATOMICAL STRUCTURES, each of which is incorporated herein byreference in its entirety and made a part of this specification.

BACKGROUND

Optical fibers have been used in conjunction with laser systems to treatvenous reflux for several years. The procedure involves placing anoptical fiber in the vein and transmitting laser light through the fiberto the vein walls, causing the vein to close. In current vein ablationsystems, an optical fiber is inserted into the vein, either bare orthrough an introducer sheath. In the latter case, the fiber tip ispositioned outside and distal of the distal end of the introducer sheathduring the procedure. In either case, when laser light is transmitted tothe fiber, the fiber tip may become very hot, potentially causing itscladding and/or buffer material to burn inside the patient's body. Inaddition, if a hot fiber tip contacts the vein wall, it may causeperforations which can result in bruising and patient discomfort.

SUMMARY

The present disclosure includes, in one embodiment, an apparatus fortreating a hollow anatomical structure. The apparatus comprises a shaftsuitable for insertion into the hollow anatomical structure. The shafthas an internal lumen, a proximal end and a distal end. The apparatusfurther comprises an optical fiber located in the lumen. The opticalfiber has a light emitting tip which is located in a distal region ofthe shaft lumen and proximal of the distal end of the shaft.

At least a portion of a sidewall of the shaft distal of the lightemitting tip can optionally be transmissive of light. In such avariation the apparatus can optionally further comprise a laser lightgenerator coupled to the optical fiber, wherein the portion of thesidewall is transmissive of at least one wavelength of light output bythe generator.

The shaft of the apparatus can optionally further comprise an opening inthe distal end of the shaft, and the distal tip of the optical fiber canoptionally be spaced proximally from the opening by a distance suitableto substantially prevent buildup of proteins, coagulum and/orcarbonization on the optical fiber tip, e.g., 2 mm to 20 mm, 2 mm to 10mm, 2 mm to 8 mm, 2 mm to 5 mm, 2 mm to 4 mm, or 3 mm. The apparatus canfurther optionally comprise a fluid flow space in the shaft between theoptical fiber and a sidewall of the shaft, and the fluid flow space canbe in fluid communication with the opening such that fluid in the spacecan flow distally through the shaft and exit the shaft via the opening.Such an apparatus can further optionally comprise a liquid source influid communication with the fluid flow space and located proximal ofthe space. Such an apparatus can further optionally comprise a flow ofliquid proceeding from the liquid source to the fluid flow space and outthe opening of the shaft. The flow of liquid can optionally have a flowrate in the fluid flow space suitable to substantially preventcarbonization and protein buildup on the distal tip of the opticalfiber; e.g., a flow rate of 5-60 cc/hour, 5-40 cc/hour, 10-30 cc/hour,15-25 cc/hour, or about 20 cc/hour. Where employed, the liquid sourcecan be configured to provide a fixed and predetermined flow rate, suchas any of the flow rates specified above.

In another embodiment, an apparatus for treating a hollow anatomicalstructure comprises a cannula suitable for insertion into the hollowanatomical structure. The cannula has a distal end and a proximal end,and a lumen therein. The apparatus further comprises a light deliverydevice located at least partially in the cannula. The light deliverydevice has a light emitting portion. The light emitting portion of thelight delivery device is located in the lumen of the cannula proximal ofthe distal end of the cannula. The apparatus further comprises a lightfield emanating distally from the light emitting portion of the lightdelivery device.

The cannula can optionally comprise an opening at the distal end of thecannula, and the light field can extend through the opening.

The cannula can optionally comprise a light-transmissive distal portion,and at least a portion of the light field can extend through thelight-transmissive distal portion. The light-transmissive distal portioncan optionally be sufficiently transmissive of light (optionallyincluding one or more of the wavelengths 810 nm, 940 nm, 980 nm, 1320nm, or 1470 nm, or the wavelength ranges 400-3000 nm or 800-1500 nm) topermit heating and reduction in diameter of a target hollow anatomicalstructure such as a vein.

The light delivery device can optionally comprise an optical fiber, andthe light emitting portion can comprise a tip of the optical fiber. Insuch an apparatus the light can optionally comprise laser light.

The cannula can optionally comprise an opening at the distal end of thecannula, and the apparatus can further comprise a flow of liquidproceeding distally through the cannula, out the opening, and through atleast a portion of the light field. The flow of liquid can optionallyhave a flow rate suitable to substantially prevent carbonization andprotein buildup on the distal tip of the light delivery device; e.g., aflow rate of 5-60 cc/hour, 5-40 cc/hour, 10-30 cc/hour, 15-25 cc/hour,or about 20 cc/hour. Where employed, a liquid source can be configuredto provide a fixed and predetermined flow rate in the cannula, such asany of the flow rates specified above. In such an apparatus, the lightdelivery device can optionally comprise an optical fiber, and the lightemitting portion can comprise a tip of the optical fiber. The light canoptionally comprise laser light. Such an apparatus can furtheroptionally comprise a laser light generator coupled to the opticalfiber.

The distal tip of the light delivery device can optionally be spacedproximally from the cannula opening by a distance suitable tosubstantially prevent buildup of proteins, coagulum and/or carbonizationon the light delivery device tip, e.g., 2 mm to 20 mm, 2 mm to 10 mm, 2mm to 8 mm, 2 mm to 5 mm, 2 mm to 4 mm, or about 3 mm.

In another embodiment, an apparatus for treating a hollow anatomicalstructure comprises a kit including a sheath and an optical fiber. Thesheath has a distal end suitable for insertion into the hollowanatomical structure, a reference point located proximal of the distalend on a portion of the sheath intended to remain outside the hollowanatomical structure during use, and a lumen configured to receive theoptical fiber. The lumen extends to the distal end of the sheath. Theoptical fiber has a distal tip suitable for light emission. The opticalfiber bears a mark which is positioned along the length of the fibersuch that, when the mark is aligned with the reference point, the distaltip of the fiber is located within the lumen, proximal of the distal endof the sheath.

The distal tip of the fiber can optionally be located 2 mm to 20 mm, 2mm to 10 mm, 2 mm to 8 mm, 2 mm to 5 mm, 2 mm to 4 mm, or about 3 mmproximal of the distal end of the sheath when the mark is aligned withthe reference point.

The lumen can optionally extend through a shaft of the sheath, and atleast a distal portion of the shaft can be transmissive of thewavelength(s) of light emitted by the apparatus during use. The distalportion can optionally be sufficiently transmissive of light (optionallyincluding one or more of the wavelengths 810 nm, 940 nm, 980 nm, 1320nm, or 1470 nm, or the wavelength ranges 400-3000 nm or 800-1500 nm) topermit heating and reduction in diameter of a target hollow anatomicalstructure such as a vein.

The lumen can optionally extend through a shaft of the sheath, and atleast a distal portion of the shaft can be formed from material which issubstantially transparent or translucent to visible light.

The kit can optionally be contained in a sterile package.

The sheath can optionally comprise an introducer sheath. In such anapparatus, the sheath can optionally comprise a hub and a sidearmconnected to the hub, with the sidearm being in fluid communication withthe lumen of the sheath.

The sheath can optionally have an opening at its distal end.

In another embodiment, an apparatus for treating a hollow anatomicalstructure comprises a kit including a sheath and an optical fiber. Thesheath has a distal end suitable for insertion into the hollowanatomical structure, and a lumen configured to receive the opticalfiber. The lumen extends to the distal end of the sheath. The lumen hasa sidewall, and at least a distal portion of the sidewall istransmissive of visible or infrared light. The distal portion canoptionally be sufficiently transmissive of light (optionally includingone or more of the wavelengths 810 nm, 940 nm, 980 nm, 1320 nm, or 1470nm, or the wavelength ranges 400-3000 nm or 800-1500 nm) to permitheating and reduction in diameter of a target hollow anatomicalstructure such as a vein.

At least the distal portion of the sidewall can optionally besubstantially transparent or translucent to visible light.

The optical fiber can optionally have a distal tip suitable for lightemission. In such an apparatus the optical fiber can bear a mark whichis positioned along the length of the fiber such that, when the mark isaligned with a reference point of the sheath, the distal tip of thefiber is located within the lumen, proximal of the distal end of thesheath. In such an apparatus the distal tip of the fiber can optionallybe located 2 mm to 20 mm, 2 mm to 10 mm, 2 mm to 8 mm, 2 mm to 5 mm, 2mm to 4 mm, or about 3 mm proximal of the distal end of the sheath, whenthe mark is aligned with the reference point.

The kit can optionally be contained in a sterile package.

The sheath can optionally comprise an introducer sheath. In such anapparatus, the sheath can optionally comprise a hub and a sidearmconnected to the hub, wherein the sidearm is in fluid communication withthe lumen of the sheath.

The sheath can optionally have an opening at its distal end.

The kit can optionally further comprise a liquid source configured forconnection to and fluid communication with the lumen of the sheath. Theliquid source can be further configured to provide a fixed andpredetermined liquid flow rate in the sheath. The fixed andpredetermined liquid flow rate can optionally be suitable tosubstantially prevent carbonization and protein buildup on the distaltip of the optical fiber; e.g., a flow rate of 5-60 cc/hour, 5-40cc/hour, 10-30 cc/hour, 15-25 cc/hour, or about 20 cc/hour.

In another embodiment, an apparatus for treating a hollow anatomicalstructure comprises a sheath and a light delivery device. The sheath isconfigured to receive the light delivery device, and the sheath has anat least partially optically transmissive distal region. The distalregion can optionally be sufficiently transmissive of light (optionallyincluding one or more of the wavelengths 810 nm, 940 nm, 980 nm, 1320nm, or 1470 nm, or the wavelength ranges 400-3000 nm or 800-1500 nm) topermit heating and reduction in diameter of a target hollow anatomicalstructure such as a vein. The light delivery device has a light emissionportion, and the light emission portion is located in the distal regionof the sheath, proximal of a distal end of the distal region.

The distal region of the sheath can optionally comprise a tube. Such atube can optionally be formed from a material which is transmissive ofvisible or infrared light, or from a material which is substantiallytransparent or translucent to visible light.

The distal region of the sheath can optionally comprise a plurality ofexpandable members surrounding the light emission portion. Theexpandable members can optionally be spaced apart from each other topermit light to pass therebetween.

The light delivery device can optionally comprise an optical fiber. Insuch an apparatus the light emission portion can optionally comprise adistal tip of the fiber.

The apparatus can optionally further comprise a fluid delivery path inthe sheath, which fluid delivery path extends distally to and beyond thelight emission portion. The apparatus can further optionally comprise aflow of liquid proceeding distally through the sheath. The flow ofliquid can optionally have a flow rate suitable to substantially preventcarbonization and protein buildup on the distal tip of the lightdelivery device; e.g., a flow rate of 5-60 cc/hour, 5-40 cc/hour, 10-30cc/hour, 15-25 cc/hour, or about 20 cc/hour. Where employed, a liquidsource can be configured to provide a fixed and predetermined flow ratein the sheath, such as any of the flow rates specified above.

In another embodiment, a method of treating a hollow anatomicalstructure comprises inserting into the hollow anatomical structure anapparatus comprising a sheath having a distal end, and a light emissionportion disposed in the sheath proximal of the distal end. The methodfurther comprises heating a wall of the hollow anatomical structure byemitting light from the light emission portion, while the light emissionportion is disposed in the sheath proximal of the distal end.

The method can optionally further comprise delivering a liquid throughthe sheath and past the light emission portion. In such a method,emitting light can optionally comprise passing at least a portion of thelight through the liquid, and heating the liquid with the light. Such amethod can further optionally comprise delivering the heated liquid tothe wall of the hollow anatomical structure and thereby heating the wallof the hollow anatomical structure.

Delivering the liquid can further optionally comprise delivering theliquid at a flow rate in the sheath suitable to substantially preventcarbonization and protein buildup on the distal tip of the lightemission portion; e.g., a flow rate of 5-60 cc/hour, 5-40 cc/hour, 10-30cc/hour, 15-25 cc/hour, or about 20 cc/hour. The liquid can be deliveredvia a liquid source can be configured to provide a fixed andpredetermined flow rate in the sheath, such as any of the flow ratesspecified above.

In the method, emitting light can optionally comprise passing at least aportion of the light through a sidewall of the sheath.

The light emission portion of the apparatus can optionally comprise atip of an optical fiber, with the optical fiber being disposed in thesheath.

In the method, the hollow anatomical structure can optionally comprise avein or a varicose vein.

The method can optionally further comprise preventing, with the sheath,the light emission portion from contacting the wall of the hollowanatomical structure during the emitting light.

In another embodiment, a method of treating a hollow anatomicalstructure comprises positioning in the hollow anatomical structure atreatment system comprising a sheath and an optical fiber with a distaltip located in a lumen of the sheath; and establishing a liquid flow of5-60 cc/hour, 5-40 cc/hour, 10-30 cc/hour, 15-25 cc/hour, or about 20cc/hour proceeding distally through the sheath lumen, past the distaltip of the optical fiber. The method further comprises: while the distaltip is located in the lumen of the sheath and the liquid flow ispresent, emitting light energy from the optical fiber, and therebyheating a wall of the hollow anatomical structure.

The sheath can optionally comprise a distal tip opening and the distaltip of the optical fiber can be located 2 mm to 20 mm, 2 mm to 10 mm, 2mm to 8 mm, 2 mm to 5 mm, 2 mm to 4 mm, or about 3 mm proximal of thedistal tip opening of the sheath, when emitting the light energy fromthe optical fiber.

The method can optionally further comprise reducing the diameter of thehollow anatomical structure via the heating. The hollow anatomicalstructure can optionally comprise a vein.

Establishing the liquid flow can comprise establishing the liquid flowwith a liquid source configured to provide liquid at a fixed andpredetermined flow rate. The flow rate can be 5-60 cc/hour, 5-40cc/hour, 10-30 cc/hour, 15-25 cc/hour, or about 20 cc/hour.

The method can optionally further comprise contacting the liquid flowwith the distal tip of the optical fiber. At least a portion of thedistal tip of the optical fiber can comprise bare core material of thefiber, and contacting the liquid flow with the distal tip of the fibercan comprise contacting the liquid flow with the bare core material.Establishing the liquid flow can comprise establishing the liquid flowdistally along the length of the sheath, and then through a spacebetween the distal tip of the optical fiber and an inner wall of thesheath. Establishing the liquid flow can further comprise establishingthe flow out an opening in a distal region of the sheath. The openingcan be located in a distal tip of the sheath and oriented transverse toa longitudinal axis of the sheath.

In one variation of the method, emitting light energy from the opticalfiber can comprise passing at least a portion of the light energythrough a sidewall of the sheath. The portion of the light energypassing through the sidewall can be sufficient to reduce the diameter ofthe hollow anatomical structure.

In one variation of the method, establishing the liquid flow cancomprise establishing the liquid flow in a space in the sheath lumenbetween the optical fiber and an inner wall of the sheath.

One variation of the method further comprises minimizing carbonizationon the distal tip of the optical fiber.

In another embodiment, a method of treating a hollow anatomicalstructure comprises positioning in the hollow anatomical structure atreatment system comprising a sheath and an optical fiber with a distaltip located in a lumen of the sheath; inhibiting carbonization andprotein buildup on the distal tip of the optical fiber by establishing aliquid flow proceeding distally through the sheath lumen, past thedistal tip of the optical fiber; and, while the distal tip is located inthe lumen of the sheath and the liquid flow is present, emitting lightenergy from the optical fiber, and thereby heating a wall of the hollowanatomical structure.

In variations of the method, establishing the liquid flow comprisesestablishing a flow of 5-60 cc/hour, 5-40 cc/hour, 10-30 cc/hour, 15-25cc/hour, or about 20 cc/hour.

In variations of the method, the sheath comprises a distal tip openingand the distal tip of the optical fiber is located 2 mm to 20 mm, 2 mmto 10 mm, 2 mm to 8 mm, 2 mm to 5 mm, 2 mm to 4 mm, or about 3 mmproximal of the distal tip opening of the sheath, when emitting thelight energy from the optical fiber.

The method can further optionally comprise reducing the diameter of thehollow anatomical structure via the heating. The hollow anatomicalstructure can optionally comprise a vein.

The method can further comprise contacting the liquid flow with thedistal tip of the optical fiber. Optionally, at least a portion of thedistal tip of the optical fiber comprises bare core material of thefiber, and contacting the liquid flow with the distal tip of the fibercomprises contacting the liquid flow with the bare core material. As afurther option, establishing the liquid flow can comprise establishingthe liquid flow distally along the length of the sheath, and thenthrough a space between the distal tip of the optical fiber and an innerwall of the sheath. Establishing the liquid flow can still furthercomprise establishing the flow out an opening in a distal region of thesheath. The opening can be located in a distal tip of the sheath andoriented transverse to a longitudinal axis of the sheath.

In one variation of the method, emitting light energy from the opticalfiber can comprise passing at least a portion of the light energythrough a sidewall of the sheath. The portion of the light energypassing through the sidewall can be sufficient to reduce the diameter ofthe hollow anatomical structure.

In one variation of the method, establishing the liquid flow comprisesestablishing the liquid flow in a space in the sheath lumen between theoptical fiber and an inner wall of the sheath.

Establishing the liquid flow can comprise establishing the liquid flowwith a liquid source configured to provide liquid at a fixed andpredetermined flow rate. The flow rate can be 5-60 cc/hour, 5-40cc/hour, 10-30 cc/hour, 15-25 cc/hour, or about 20 cc/hour.

Another embodiment comprises an apparatus for treating a hollowanatomical structure. The apparatus comprises a sheath having an innerlumen, the sheath being sized and configured for insertion into thehollow anatomical structure; an optical fiber positioned in the lumen ofthe sheath, a distal tip of the fiber being positioned in a distalportion of the sheath; and a liquid flow advancing distally along thelumen of the sheath, the distal tip of the fiber contacting the liquidflow, the liquid flow having a flow rate of 5-60 cc/hour, 5-40 cc/hour,10-30 cc/hour, 15-25 cc/hour, or about 20 cc/hour.

In one variation of the apparatus, at least the distal portion of thesheath has a sidewall which is highly transmissive of light. Thesidewall can be sufficiently transmissive of light to allow heating andreduction in diameter of the hollow anatomical structure. Additionallythe sidewall can be sufficiently transmissive of light in at least oneof the wavelengths 810 nm, 940 nm, 980 nm, 1320 nm, and 1470 nm, or inat least one of the wavelength ranges 400-3000 nm and 800-1500 nm topermit heating and reduction in diameter of the hollow anatomicalstructure.

The sheath can optionally comprise a distal tip opening and the distaltip of the optical fiber can be located 2 mm to 20 mm, 2 mm to 10 mm, 2mm to 8 mm, 2 mm to 5 mm, 2 mm to 4 mm, or about 3 mm proximal of thedistal tip opening of the sheath. The liquid flow can optionally advancethrough the distal tip opening and out the sheath.

The apparatus can optionally further comprise a beam of light emanatingfrom the optical fiber, the beam of light having sufficient intensity tofacilitate heating and reduction in diameter of the hollow anatomicalstructure. At least a portion of the beam of light can pass through asidewall of the sheath.

The hollow anatomical structure can optionally comprise a vein.

At least a portion of the distal tip of the optical fiber can comprisebare core material of the fiber, and the liquid flow can contact thebare core material.

The liquid flow can extend distally within the lumen of the sheath, andthrough a space between the distal tip of the optical fiber and asidewall of the sheath. At least a portion of the sidewall alongside thedistal tip of the optical fiber can be sufficiently transmissive oflight to allow heating and reduction in diameter of the hollowanatomical structure. The sidewall portion can be sufficientlytransmissive of light in at least one of the wavelengths 810 nm, 940 nm,980 nm, 1320 nm, and 1470 nm, or at least one of the wavelength ranges400-3000 nm and 800-1500 nm to permit heating and reduction in diameterof the hollow anatomical structure.

The apparatus can optionally further comprise a liquid source in fluidcommunication with the lumen of the sheath. The liquid source can beconfigured to provide a fixed and predetermined liquid flow rate in thesheath, e.g., a flow rate of 5-60 cc/hour, 5-40 cc/hour, 10-30 cc/hour,15-25 cc/hour, or about 20 cc/hour.

Another embodiment comprises an apparatus for treating a hollowanatomical structure. The apparatus comprises a sheath having an innerlumen, the sheath being sized and configured for insertion into thehollow anatomical structure; an optical fiber positioned in the lumen ofthe sheath, a distal tip of the fiber being positioned in a distalportion of the sheath; and a liquid flow advancing distally along thelumen of the sheath, the distal tip of the fiber contacting the liquidflow, the liquid flow having a flow rate suitable to inhibitcarbonization and protein buildup on the distal tip of the opticalfiber.

The liquid flow rate can optionally be 5-60 cc/hour, 5-40 cc/hour, 10-30cc/hour, 15-25 cc/hour, or about 20 cc/hour.

At least the distal portion of the sheath can have a sidewall which ishighly transmissive of light. Such a sidewall can be sufficientlytransmissive of light to allow heating and reduction in diameter of thehollow anatomical structure. Such a sidewall can be sufficientlytransmissive of light in at least one of the wavelengths 810 nm, 940 nm,980 nm, and 1320 nm, or at least one of the wavelength ranges 400-3000nm and 800-1500 nm to permit heating and reduction in diameter of thehollow anatomical structure.

The sheath can optionally comprise a distal tip opening and the distaltip of the optical fiber can be located 2 mm to 20 mm, 2 mm to 10 mm, 2mm to 8 mm, 2 mm to 5 mm, 2 mm to 4 mm, or about 3 mm proximal of thedistal tip opening of the sheath. The liquid flow can advance throughthe distal tip opening and out the sheath.

The apparatus can optionally further comprise a beam of light emanatingfrom the optical fiber, the beam of light having sufficient intensity tofacilitate heating and reduction in diameter of the hollow anatomicalstructure. At least a portion of the beam of light can pass through asidewall of the sheath.

The hollow anatomical structure can comprise a vein.

In one variation of the apparatus, at least a portion of the distal tipof the optical fiber comprises bare core material of the fiber, and theliquid flow contacts the bare core material.

In one variation of the apparatus, the liquid flow extends distallywithin the lumen of the sheath, and through a space between the distaltip of the optical fiber and a sidewall of the sheath.

In one variation of the apparatus, at least a portion of the sidewallalongside the distal tip of the optical fiber is sufficientlytransmissive of light to allow heating and reduction in diameter of thehollow anatomical structure. The sidewall portion can be sufficientlytransmissive of light in at least one of the wavelengths 810 nm, 940 nm,980 nm, 1320 nm, and 1470 nm, or at least one of the wavelength ranges400-3000 nm or 800-1500 nm to permit heating and reduction in diameterof the hollow anatomical structure.

The apparatus can optionally further comprise a liquid source in fluidcommunication with the lumen of the sheath. The liquid source can beconfigured to provide a fixed and predetermined liquid flow rate in thesheath, e.g., a flow rate of 5-60 cc/hour, 5-40 cc/hour, 10-30 cc/hour,15-25 cc/hour, or about 20 cc/hour.

In another embodiment, an apparatus for treating a hollow anatomicalstructure comprises a sheath having an elongate shaft defining aninternal lumen. The shaft has a sidewall, a proximal portion, and adistal portion, the sidewall being more transmissive of therapeuticlight energy in the distal portion than in the proximal portion. Thedistal portion of the shaft forms a distal tip of the shaft and has adistal-facing opening at the distal tip. The apparatus further comprisesan optical fiber disposed within and movable along the lumen. Theoptical fiber has a fiber tip located in the distal portion of the shaftat a firing position which is 2-20 mm proximal of the distal tip of theshaft. The apparatus further comprises a light propagation path whichextends distally from the fiber tip and through the distal-facingopening.

The firing position can be a static firing position relative to sheath.

The sidewall can be made from a first material in the proximal portionand from a second material in the distal portion, the second materialbeing more transmissive of therapeutic light than the first material. Insuch a variation, the first material can be more flexible than thesecond material. The second material can be one of quartz, sapphire,synthetic fused silica, polycarbonate, polyetherethereketone,polysufone, polyarylethersulfone, polyetherimide, and polyamide-imide.The second material can optionally be transmissive of wavelengths oflight from 400 to 3000 nm, or from 800 to 1500 nm.

The optical fiber can be insertable into the hollow anatomical structureseparately from the sheath.

The shaft can be sized for insertion into a vein. In such a variation,the outer diameter of the shaft can be less than 5 mm.

The apparatus can further comprise a liquid flow advancing distallyalong the shaft lumen and contacting the fiber tip. Such an apparatuscan further comprise a liquid source in fluid communication with thelumen, the liquid source being configured to provide the liquid flow ata fixed and predetermined liquid flow rate. The liquid flow rate canoptionally be 5-60 cc/hr. In one variation, the liquid source cancomprise a saline bag fluidly coupled to the shaft lumen through a flowregulator. The flow regulator can comprise a flow restriction fluidlycoupling the saline bag to the lumen. The flow restriction can comprisean orifice having a predetermined effective opening that is sized toprovide the predetermined liquid flow rate. The liquid source cancomprise a liquid reservoir and a liquid flow path from the reservoir tothe shaft lumen, and the flow restriction comprises an orifice of afixed size positioned in the flow path, the orifice size being smallerthan that of the rest of the liquid flow path.

The apparatus can further comprise a position limiter configured tolimit the position of the fiber tip relative to the distal tip of theshaft at the firing position. In one variation, the position limiter cancomprise a stop configured to limit the distal movement of the opticalfiber within the shaft lumen when the fiber tip is at the firingposition The stop can comprise cooperating structures of the opticalfiber and the distal shaft portion that are configured to limit therelative insertion of the fiber tip within the lumen to the firingposition. The stop can optionally be located 12 mm from the distal tipof the optical fiber, or within 10-20 mm of the distal tip of theoptical fiber.

The fiber tip can be optically coupled to the distal-facing opening toform the light propagation path.

In another embodiment, a method of treating a hollow anatomicalstructure comprises inserting a sheath with a distal end into the hollowanatomical structure, inserting an optical fiber into the sheath, andpositioning a tip of the optical fiber at a firing position anywherefrom 2-20 mm proximal of the distal end. The method further comprisesemitting light energy from the fiber tip while the tip is disposed inthe sheath proximal of the distal end and withdrawing the sheath andoptical fiber along the hollow anatomical structure while emitting thelight energy.

The method can further comprise maintaining the position of the fibertip in the firing position during the emitting and the withdrawing.

The insertion of the optical fiber in the sheath optionally occurs priorto inserting the sheath into the hollow anatomical structure. In such amethod, the optical fiber can be moveable with respect to the sheathafter the optical fiber is inserted into the sheath.

The insertion of the sheath into the hollow anatomical structureoptionally occurs prior to inserting the optical fiber into the sheath.

The emitting can comprise emitting light energy through a sidewall ofthe sheath.

The emitting can comprise emitting light energy through a distal portionof a sidewall of the sheath that is more transmissive of light energythan is a proximal portion of the sidewall.

The method can further comprise establishing a liquid flow proceedingdistally through the sheath and past the tip of the optical fiber. Insuch a method, the establishing can further comprise providing apredetermined liquid flow rate via a liquid source. The predeterminedflow rate can be fixed. The predetermined liquid flow rate canoptionally be provided at 5-60 cc/hour.

The emitting can comprise emitting light energy distally from the fibertip. In one variation, the emitting light energy distally can compriseemitting light energy through a distal-facing opening formed in thedistal end of the sheath.

The emitting can comprise emitting light energy into a wall of thehollow anatomical structure.

In another embodiment, an apparatus for treating a blood vesselcomprises a sheath defining an inner lumen and having a proximal portionand a distal portion, with the sheath configured for insertion into theblood vessel. The apparatus further comprises an optical fiberpositioned in the lumen and having a distal tip positioned in the distalportion. The apparatus further comprises a liquid flow advancingdistally along the lumen and contacting the distal tip, and a liquidsource in fluid communication with the inner lumen, the liquid sourceconfigured to provide the liquid flow at a predetermined liquid flowrate of 5-60 cc/hour.

The predetermined liquid flow rate can be fixed.

The proximal portion of the sheath can be formed from a first materialand the distal portion of the sheath can be formed from a secondmaterial that is more transmissive of light energy than the firstmaterial. The proximal portion and the distal portion can haveapproximately the same outer diameter.

The apparatus can further comprise a flow path from the liquid source tothe sheath, the flow path having a flow passage of a predetermined sizethat restricts the liquid flow to provide the predetermined liquid flowrate. In one variation, at least a portion of the flow passage can besmaller than the remainder of the flow path from the liquid source tothe sheath. The flow passage can comprise a channel having a fixed size.The channel can optionally comprise a capillary tube. Such an apparatuscan further comprise a flow restrictor member disposed in the channel.In another variation, the liquid source can be non-motorized. Such aliquid source can comprise a liquid reservoir, and the flow of liquidfrom the liquid reservoir can be driven by at least one of gravity andcompression of the liquid reservoir. The liquid reservoir can comprise asaline bag. The saline bag can be fluidly coupled to the inner lumenthrough a flow regulator. The flow regulator can comprise a flowrestriction fluidly coupling the saline bag to the lumen. The flowrestriction can comprise an orifice having a predetermined effectiveopening that is sized to provide the predetermined liquid flow rate.

The optical fiber can be moveable with respect to the sheath.

The distal sheath portion can form a distal tip of the sheath and canhave a distal-facing opening at the distal tip of the sheath throughwhich the liquid flow can pass. In one variation, the distal tip of theoptical fiber and the sheath can define a light propagation path whichextends distally from the distal tip of the optical fiber and throughthe distal-facing opening.

In another embodiment, a method of treating a hollow anatomicalstructure comprises positioning a treatment system in the hollowanatomical structure, the treatment system comprising a sheath having alumen and an optical fiber with a distal tip located in the lumen. Themethod further comprises establishing a liquid flow at a liquid flowrate of 5-60 cc/hour proceeding distally through the lumen and past thedistal tip. The method further comprises emitting light energy from theoptical fiber, thereby causing heating of a wall of the hollowanatomical structure, while the distal tip is located in the lumen andthe liquid flow is present. The method further comprises withdrawing thetreatment system along the hollow anatomical structure while emittingthe light energy.

The establishing can further comprise providing the liquid flow atpredetermined liquid flow rate. The predetermined liquid flow rate canoptionally be fixed. The providing can further comprise restricting theliquid flow from a liquid reservoir to the sheath lumen to provide thefixed and predetermined liquid flow rate. In one variation, therestricting can further comprise flowing liquid through a smallerdiameter portion of a flow passage coupling the liquid reservoir to thesheath lumen. In another variation, the restricting can further compriseflowing liquid through a channel having a fixed size. The channel canoptionally be rigid. The restricting can further comprise flowing liquidthrough a capillary tube. The restricting can further comprise flowingliquid past a flow restrictor member disposed in the channel.

The establishing can further comprise providing the liquid flow ratefrom a non-motorized liquid source. In one variation, the liquid sourcecan comprise a liquid reservoir and the providing further comprisesdriving the flow of liquid from the liquid reservoir by at least one ofgravity and compression of the liquid reservoir. In another variation,the providing can further comprise flowing liquid from a saline bag.

The method can further comprise maintaining the position of the distalfiber tip relative to the distal end of the sheath during the emittingand the withdrawing.

The positioning can comprise sequentially inserting the optical fiber inthe sheath and inserting the sheath into the hollow anatomicalstructure.

The positioning can comprise sequentially inserting the sheath into thehollow anatomical structure and inserting the optical fiber into thesheath.

The emitting can comprise emitting light energy through a sidewall ofthe sheath.

The emitting can comprise emitting light energy through a distal portionof the sheath. In such a method, the emitting light energy through adistal portion of the sheath can comprise emitting light energy througha portion of the distal portion that is transmissive of light energy.

The emitting can comprise emitting light energy distally from the distaltip. In such a method, the emitting can comprise emitting light energythrough a distal-facing opening formed in a distal portion of thesheath.

The emitting can comprises emitting light energy into a wall of thehollow anatomical structure.

The emitting can comprise emitting light energy radially from the distaltip.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of one embodiment of a system for treatinga hollow anatomical structure.

FIG. 2 is a detailed perspective view of a distal portion of a sheathand a light delivery device of the system of FIG. 1.

FIG. 3 is a side sectional view of the distal portion of FIG. 2.

FIG. 4 is a side sectional view of a distal portion of anotherembodiment of the sheath.

FIG. 4A is a schematic view of another embodiment of a system fortreating a hollow anatomical structure having a liquid source.

FIG. 4B is a schematic view of a liquid source usable with the systemsof FIGS. 1-4A and 5-28.

FIG. 4C is a schematic view of a flow regulator usable with the liquidsource of FIG. 4B.

FIG. 4D is a detailed view of FIG. 4C.

FIG. 4E is a schematic view of another embodiment of a flow regulatorusable with the liquid source of FIG. 4B with a bypass controller in aclosed position.

FIG. 4F is a detailed view of FIG. 4E with a bypass controller in anopen position.

FIG. 5 is a detailed perspective view of a distal portion of anotherembodiment of the sheath.

FIG. 6 is a side sectional view of the sheath of FIG. 5.

FIG. 7A is a side view of the sheath of FIG. 5.

FIG. 7B is a side view of the sheath of FIG. 5, with expandable membersthereof in a retracted configuration.

FIG. 8A is a side view of another embodiment of the sheath.

FIG. 8B is a side view of the sheath of FIG. 8A, with an expandablecollar thereof in the expanded configuration.

FIG. 9A is a side view of another embodiment of the sheath.

FIG. 9B is a side view of the sheath of FIG. 9A, with an expandablespring thereof in the expanded configuration.

FIG. 10A is a side view of another embodiment of the sheath.

FIG. 10B is a side view of the sheath of FIG. 10A, with a balloonthereof in the inflated configuration.

FIG. 11 is a perspective view of another embodiment of the sheath ofFIG. 2.

FIG. 12A is a perspective view of a distal portion of another embodimentof the sheath and another embodiment of the light delivery device.

FIG. 12B is a side sectional view of the sheath and the light deliverydevice of FIG. 12A.

FIG. 13 is a side sectional view of a distal portion of anotherembodiment of the sheath with the light delivery device of FIG. 2.

FIG. 14A is a side sectional view of a distal portion of anotherembodiment of the sheath with the light delivery device of FIG. 2.

FIG. 14B is a side sectional view of a distal portion of the embodimentof the sheath shown in FIG. 14A with a light scattering material locatedinside the sheath.

FIG. 15 is a side sectional view of a distal portion of anotherembodiment of the sheath with the light delivery device of FIG. 12A.

FIG. 16 is a side sectional view of a distal portion of anotherembodiment of the sheath with the light delivery device of FIG. 12A.

FIG. 17A is a perspective view of a distal portion of another embodimentof the light delivery device.

FIG. 17B is a side sectional view of the light delivery device of FIG.17A.

FIG. 18 is a side sectional view of a distal portion of anotherembodiment of the light delivery device.

FIG. 19 is a side sectional view of a distal portion of anotherembodiment of the light delivery device.

FIG. 20A is a perspective view of a distal portion of another embodimentof the light delivery device.

FIG. 20B is a side sectional view of the light delivery device of FIG.20A.

FIG. 21A is a side sectional view of a distal portion of anotherembodiment of the light delivery device comprising a position limiter.

FIG. 21B is a perspective view of a portion of the position limiter ofFIG. 21 A.

FIG. 22A is a side sectional view of a distal portion of anotherembodiment of the light delivery device comprising a position limiter.

FIG. 22B is a perspective view of a portion of the position limiter ofFIG. 22A.

FIG. 22C is a front view of a portion of the position limiter of FIG.22A.

FIG. 23A is a side sectional view of a distal portion of anotherembodiment of the light delivery device comprising a position limiter.

FIG. 23B is a perspective view of a portion of the position limiter ofFIG. 23A.

FIG. 24A is a side sectional view of a distal portion of anotherembodiment of the light delivery device comprising a position limiter.

FIG. 24B is a perspective view of a portion of the position limiter ofFIG. 24A.

FIG. 25A is a side sectional view of a distal portion of anotherembodiment of the light delivery device comprising a position limiter.

FIG. 25B is a perspective view of a portion of the position limiter ofFIG. 25A.

FIG. 25C is a front view of a portion of the position limiter of FIG.25A.

FIG. 25D is a top view of a portion of the position limiter FIG. 25A.

FIG. 26A is a side sectional view of a distal portion of anotherembodiment of the light delivery device comprising a position limiter.

FIG. 26B is a perspective view of a portion of the position limiter ofFIG. 26A.

FIG. 27 is a side sectional view of a distal portion of anotherembodiment of the light delivery device comprising a position limiter.

FIG. 28 is a side sectional view of a distal portion of anotherembodiment of the light delivery device comprising a position limiter.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The features of the systems and methods will now be described withreference to the drawings summarized above. The drawings, associateddescriptions, and specific implementation are provided to illustratepreferred embodiments of the invention(s) disclosed herein, and not tolimit the scope of the patent protection sought in connection with thisspecification.

In addition, methods and functions of treatment systems or devicesdescribed herein are not limited to any particular sequence, and theacts relating thereto can be performed in other sequences that areappropriate. For example, described acts may be performed in an orderother than that specifically disclosed, or multiple acts may be combinedin a single act.

One embodiment of a system 100 for treating a hollow anatomicalstructure or “HAS” (e.g., a blood vessel, a vein, a varicose vein, afallopian tube, ovarian vein, etc.) is depicted in FIGS. 1, 2 and 3. Thedepicted embodiment of the system 100 includes an introducer sheath 110having a preferably tubular and flexible shaft 112, a distal end ofwhich includes a protective distal tip portion 114. The sheath 110preferably further comprises a hub 120 attached to a proximal end of theshaft 112, and a sidearm 122 which can include a port 124 to facilitateintroduction of fluids into the sidearm 122. In the depicted embodimentthe hub 120 is configured to permit fluid communication between thesidearm 122 and the shaft 112 such that a fluid introduced into the port124 of the sidearm 122 can flow into a lumen 116 (see FIG. 3) of theshaft 112. An appropriate connector, such as a Luer fitting (not shown)can be included at the port 124 (or on the hub 120 instead of thesidearm 122) to permit connection of medical apparatus, fluid sources,etc. to the sidearm 122. The sheath 110 can be sized for insertion intoa HAS, and can have an outer diameter of 1-5 mm.

The system 100 depicted in FIGS. 1-3 can further comprise a lightdelivery device 150 disposed in the lumen 116 of the shaft 112. In thedepicted embodiment the light delivery device 150 comprises an opticalfiber 152, which can be coupled to a laser light generator 154. Whereemployed, the optical fiber 152 can extend proximally through the hub120 of the introducer sheath 110 to the laser light generator 154, toconduct laser energy output by the generator 154 through the shaft 112to the desired treatment area as will be discussed in greater detailbelow. A hemostatic seal or the like can be provided in the hub 120 toprovide a seal around the fiber 152 and prevent fluid in the shaft lumen116 from escaping proximally beyond the hub 120. As an alternative tothe depicted optical fiber 152, the light delivery device 150 cancomprise a small laser light source or other light source disposed inthe lumen 116 of the shaft 112.

In the depicted embodiment, the optical fiber 152 comprises alight-conducting optical core 156 formed from glass, silica or othersuitable light-conducting material(s), surrounded by cladding 158 madefrom silica or polymers or the like, to promote internal reflectionwithin the core 156. A protective jacket 160 surrounds the cladding 158and the core 156. The jacket 160 is optionally stripped back to expose adistal tip portion of the cladding 158 and core 156, and this distal tipportion is typically between about 2 mm and 8 mm in length.Alternatively, the optical fiber 152 can be employed without any of thejacket 160 stripped from the distal fiber tip, e.g. with only the distalface of the core 156 exposed at the distal tip. The core 156 preferablyterminates in an unclad, distal light emitting tip 162. In operation,light 170 (e.g. laser light) propagates distally down the core 156 ofthe fiber 152, exits the core 156 at the light emitting tip 162 andadvances generally distally from the tip 162. The tip 162 is preferablya generally flat surface oriented generally orthogonal to thelongitudinal axis of the fiber 152. Alternatively, however, the tip 162can also be formed, shaped, or ground to create facets, or a sphericalor prismatic tip face to direct a portion of the light in the radialdirection.

The distal tip portion 114 of the shaft 112 is preferably transparentto, or otherwise highly transmissive of, the wavelength(s) of light 170emitted via the tip 162 of the fiber 152 (or other light delivery device150) during operation of the system 100. Such wavelengths of light 170can optionally range from 400 to 3000 nm, or from 800 to 1500 nm. Thedistal tip portion 114 can also be sufficiently transmissive of suchwavelength(s) of light (or of specific suitable therapeutic wavelengthssuch as 810 nm, 940 nm, 980 nm, 1320 nm and/or 1470 nm) to permitheating and reduction in diameter of a target hollow anatomicalstructure such as a vein, and/or to avoid melting and/or burning thedistal tip portion 114 when light (optionally including light in theabove-noted wavelength(s) is emanating from the fiber 152 at sufficientintensity to lead to heating and reduction in diameter of the HAS orvein. Suitable materials for use in forming the distal tip portion 114include, without limitation, quartz, sapphire, borosilicate glass(PYREX(™)), synthetic fused silica, polycarbonate, polyetheretherketone,polysulfone, polyarylethersulfone, polyetherimide, and polyamide-imides.The distal tip portion 114 can optionally comprise a tube with a wallthickness of 0.2-1.0 mm.

Some or all of the light 170 can propagate from the tip 162, distallyand/or outwardly through the sidewalls and/or end of the distal tipportion 114 and to the desired treatment area. The fiber tip 162 cantherefore remain disposed within the distal tip portion 114 of the shaft112 during treatment, and the distal tip portion 114 can protect the hotfiber tip 162 from contact with the inner wall of the vein or othertarget HAS (and vice versa).

In the depicted embodiment, the fiber tip 162 is spaced proximally froma distal end 172 of the distal tip portion 114 by a distance X of 2 mmto 20 mm. The distal tip portion 114 can further optionally include anopening 174 to permit light and/or liquids to flow from the tip portion114, and/or a tapered tip region 176 to facilitate easy and atraumaticinsertion of the shaft 112 into small-diameter HAS's.

Preferably, the light delivery device 150 and the lumen 116 of the shaft112/tip portion 114 are sized so that a fluid delivery space 178 isprovided between the light delivery device 150 and the inner wall of theshaft 112/tip portion 114. In such an embodiment, a liquid such assaline (or any other suitable liquid) can be delivered distally throughthe shaft 112 and tip portion 114, and out the opening 174, duringdelivery of light 170 from the device 150. The delivered liquid canoptionally absorb the wavelength(s) of light 170 emitted from the device150, to a sufficient degree to induce heating and/or boiling of thedelivered liquid as it flows through the delivery space 178 and light170, and out the opening 174. The hot/boiling liquid will also tend toheat the tip portion 114. Thus, this embodiment of the system 100 can becapable of providing at least three mechanisms of therapeutic HAS wallheating: (1) hot or boiling fluid heating of the HAS walls, (2)conductive heating from the hot sheath tip 114, and (3) light or laserenergy 170 transmitted directly to the HAS walls.

By controlling the light/laser power, the distance X, liquid flow rate,and liquid starting temperature, the HAS heating zone/length can becontrolled and an optimized thermal therapy can be accomplished. Also,by selecting a preferentially water absorbing light/laser wavelength(e.g. 1320 nm, etc.) the therapy can be one in which substantially allof the light/laser energy is absorbed by the (aqueous) liquid which bothflows from the sheath opening 174 and heats the sheath tip 114 to createa heat zone for effecting tissue thermal therapy. The aforementionedparameters are preferably varied to ensure that the heating ismaintained at or around 100° C., providing a controlled therapy withminimal complications (e.g., minimizing uncontrolled high temperaturesthat cause increased depth of thermal injury leading in turn topotential pain and bruising; and avoiding fiber tip wall contact andperforations that lead to blood extravasations and bruising).

In one embodiment of a method of use of the system 100, the target HAS(e.g. a vein such as the greater saphenous vein) can first be accessedby using a suitable access technique (e.g. the standard Seldingertechnique). A guide wire is passed into the target HAS, and theintroducer sheath 110 is fed over the guidewire into the target HAS andadvanced to the desired start location. In the case of the greatersaphenous vein, the desired start location is just below thesapheno-femoral junction. The guidewire is then withdrawn from thesheath 110 and the light delivery device 150 is advanced distallythrough the hub 120 and down the shaft 112 until the device 150 isappropriately positioned within the sheath tip 114. Where the lightdelivery device 150 comprises the optical fiber 152, the fiber tip 162is positioned so that it is proximal of the distal end 172 of the tip114 by the distance X. An appropriate mark (or a projection such as aflange, slidable collar or “donut”) can be provided on a proximal regionof the fiber 152 to facilitate positioning of the fiber tip 162, suchthat alignment of the mark with the proximal edge of the hub indicatesthat the desired position of the fiber tip 162 has been reached. Asuitable lock, clamp or Touhy-Borst valve can be provided in the hub 120to prevent longitudinal movement of the fiber 152 within the sheath, andthis lock or clamp can be activated after positioning of the fiber tip162 within the sheath 110 as described above. Alternatively, the sheath110 and light delivery device 150 can be combined prior to insertion andadvanced into the target HAS together, without need for a guidewire.

Before or after placement of the optical fiber 152 or other lightdelivery device, the position of the sheath 110 relative to the desiredtreatment location can be verified using appropriate techniques such asultrasound. In addition, the target HAS can optionally be prepared fortreatment by using any desired combination of manual compression,compression bandages, and/or injection of tumescent anesthesia into thetissues surrounding the target HAS, to exsanguinate the HAS lumen (inthe case of treating blood vessels) and reduce the lumenal diameter inpreparation for heat treatment.

If desired, a liquid flow via the sidearm 122, through the sheath 110and into the HAS lumen can be commenced as described above. The lightdelivery device 150 is activated, providing light, such as laser light,at one or more appropriate wavelengths or wavelength ranges such as 810nm, 940 nm, 980 nm, 1320 nm, and/or 1470 nm, and/or 400-3000 nm or800-1500 nm, and at an appropriate power level. The assembly of thesheath 110 and device 150 is slowly withdrawn through the HAS lumen,preferably at a rate about of 0.5-5 millimeters per second. As theassembly is moved along the lumen, therapeutic heat is delivered to theHAS walls via one or more of the following: (1) heating of the HAS wallsvia any hot or boiled delivered liquid, (2) conductive heating from thehot sheath tip 114, and (3) light or laser energy 170 transmissiondirectly to the HAS walls. After the desired length of the target HAShas been treated with the therapeutic heat, the sheath 110 and device150 can be removed and appropriate post-procedural care can beadministered.

In one embodiment of the method of use of the system 100, a liquid flowsuitable to minimize, inhibit or substantially prevent buildup ofproteins, coagulum and/or carbonization on the fiber tip 162 (e.g.,having a flow rate of 5-60 cc/hour, 5-40 cc/hour, 10-30 cc/hour, 15-25cc/hour, or about 20 cc/hour) is established in the sheath 110 duringtreatment of a target HAS. As discussed in further detail below, thisliquid flow has also been found suitable to minimize, inhibit orsubstantially prevent perforation of the hollow anatomical structurebeing treated (including veins in particular). When employed with thesystem 100 depicted in FIGS. 1-3, this liquid flow advances distally,along and in contact with the distal portion of the fiber 152, in the(typically annular) fluid delivery space 178 between the distal portionof the fiber and the inner wall of the distal tip portion 114. Where thefiber 152 of the system 100 includes a stripped distal portion as shownin FIGS. 2-3, the liquid flow advances along and in contact with thecladding 158; and/or the unclad, distal light emitting tip 162 points orfaces distally toward a portion of the liquid flow located in the sheathtip 114 distal of the tip 162 such that the bare, unclad core materialwhich forms the tip 162 contacts this distal portion of the liquid flow.The liquid flow can comprise saline or any other suitable liquiddisclosed herein.

The method of use of the system 100 can also optionally includepositioning the fiber tip 162 in the sheath 112 such that the tip 162 isspaced proximally from the distal end 172 and/or opening 174 of thedistal tip portion 114 by the distance X (see FIG. 3) of 2 mm to 20 mm,2 mm to 10 mm, 2 mm to 8 mm, 2 mm to 5 mm, 2 mm to 4 mm, or 3 mm; orotherwise by a distance suitable to minimize, inhibit or substantiallyprevent buildup of proteins, coagulum and/or carbonization on the fibertip 162. This tip spacing has also been found suitable to minimize,inhibit or substantially prevent perforation of the hollow anatomicalstructure being treated (including veins in particular).

It has been found that providing an appropriate fluid flow over thedistal portion of the fiber 152, and/or properly spacing the fiber tip162 from the distal end 172 and/or opening 174 of the distal tip portion114 helps to minimize buildup of coagulum and/or carbonized bloodcomponents on the fiber tip 162. This in turn minimizes perforation ofthe treated hollow anatomical structure, particularly in veins, possiblydue to the elimination of the enlarged hot carbonized mass oftenobserved on the tip of an optical fiber used in treatment of a hollowanatomical structure. Accordingly, a method of minimizing carbonizationon the fiber tip 162 and/or minimizing HAS/vein perforation (or a stepof minimizing carbonization and/or HAS/vein perforation, as part of amethod of use of the system 100) can comprise establishing a liquid flowas specified above, and/or spacing the fiber tip 162 from the distal end172 and/or opening 174 as specified above.

In addition, a low-carbonization or no-carbonization (or low-perforationor no-perforation) system 100 can include the optical fiber 152 disposedwithin the sheath 110, with the distal portion of the fiber 152(including at least a portion of the exposed cladding 158, and/or thelight emitting tip 162) located in the distal tip portion 114 (which canbe transparent or otherwise highly transmissive of the wavelength(s) oflight emitted from the fiber tip 162) and surrounded by (and/or incontact with) the liquid flow specified above. The fiber tip 162 can bespaced from the distal end 172 and/or distal tip opening 174 (ifpresent) of the distal tip portion 114, by the distance X specifiedabove. Where both the fluid flow and the fiber tip spacing are employed,there can exist a distal portion of the fluid flow within the distal tipportion 114 of the sheath 110, which distal portion of the fluid flowextends distally from the fiber tip 162 by the distance X. The distalportion of the fluid flow preferably contacts the fiber tip 162; wherethe fiber tip 162 is an unclad portion of the fiber core material, thedistal portion of the fluid flow contacts the fiber core material at thefiber tip 162.

FIG. 4 depicts an alternative embodiment of the system 100, which can besimilar in structure, use and function to any of the variations of thesystem 100 of FIGS. 1-3, except as further described herein. In thesystem 100 of FIG. 4, the distal tip portion 114 of the shaft 112 of thesheath 110 is substantially non-transparent to the wavelength(s) oflight emitted from the device 150 during use. The distance X between thetip 162 and the sheath distal end 172, and the angle θ through which thelight 170 is propagated, can be selected to ensure that most or all ofthe light 170 will not be transmitted to the sheath tip walls, but willexit through the opening 174 and be transmitted to the target HAS walls.

As a further variation of the system 100 of FIGS. 1-3, a light-absorbingcoating can be applied to the distal tip portion 114. The coating can beselected to absorb, highly or completely, the wavelength(s) of lightemitted by the device 150. Thus the emitted light is converted to heatin the tip portion 114 and any delivered liquid, and energy is deliveredto the target HAS walls via the hot and/or boiled liquid and/or contactwith the heated tip portion 114.

As a variation of the systems 100 of FIGS. 1-4, the shaft 112 of thesheath 110 can include two, preferably concentric, lumens. In such asheath 110, the inner lumen provides space for the fiber 152 or otherlight delivery device and the outer lumen provides a conduit for anyliquid(s) to flow. At the distal end of the shaft 112, the outer lumencommunicates with the inner lumen and sheath tip 114, allowing saline toflow around the tip 162 of the fiber 152 or other device 150.

As another variation of the systems 100 of FIGS. 1-4, the light deliverydevice 150 can be replaced with another energy application device in theform of, e.g., an electrically driven heater wire or heater coilpositioned in the sheath tip 114 in a similar manner as the strippedportion of the optical fiber 152 depicted in FIGS. 2-4. Such anelectrically driven heater wire or coil can be employed to heat thedelivered liquid and/or sheath tip as described elsewhere herein, andthereby therapeutically heat the walls of the target HAS.

As another variation of the systems 100 of FIGS. 1-4, the light deliverydevice 150 can be replaced with a thermally insulated conduit for theflow of a pre-heated liquid (e.g., saline, etc.) out the distal end ofthe sheath 110 and to treatment site. The temperature of the liquid andits flow rate can be controlled to optimize the temperature and lengthof the treatment zone at the sheath tip.

FIG. 4A depicts an alternative embodiment of the system 100, which canbe similar in structure, use and function to any of the variations ofthe system 100 of FIGS. 1-3, except as described herein. In the system100 of FIG. 4A, a liquid source 300 is provided which may be used tofacilitate delivery of the liquid flow at a desired flow rate asdiscussed above. The depicted liquid source 300 is in fluidcommunication with the inner lumen 116 of the sheath 112 via the sidearm122 or other suitable connection to the sheath 112.

FIG. 4B depicts one embodiment of the liquid source 300. The depictedliquid source 300 generally comprises a liquid reservoir 310 coupled toa plumbing network 320 which is operable to control the flow of liquidinto and out of the reservoir 310. The liquid reservoir 310, whichoptionally can be housed in a suitable housing 312, preferably comprisesa pressurizable liquid reservoir 310, such as an elastic bladder or acylinder with a spring-loaded piston received therein. Alternatively anon-elastic reservoir 310 can be employed, which can rely on gravity todrive liquid flow out of the liquid source 300.

In the depicted embodiment, the plumbing network 320 comprises a primarypassage 322 and a secondary passage 324 which are interconnected by athree-way stopcock 326. The primary passage 322 can be coupled to and influid communication with the liquid reservoir 310 via a source connector328, while the secondary passage 324 terminates in a fill connector 330,which preferably comprises a luer fitting but can comprise any suitableconnector to facilitate connection to a syringe for filling thereservoir 310. The primary passage 322 terminates in an outlet 332,which can comprise a luer connector or other hardware suitable forfacilitating fluid communication between the outlet 332 and the sheath110 or sidearm 122.

A flow regulator 340 is preferably located on the primary passage 322,and is operable to regulate the rate at which liquid flows from theliquid source 300. The flow regulator preferably provides a fixed andpredetermined flow rate through the primary passage 322, e.g., 5-60cc/hour, 5-40 cc/hour, 10-30 cc/hour, 15-25 cc/hour, or about 20cc/hour. This can be implemented via, for example, a restricted passagethrough the flow regulator 340 that, in combination with the fluidpressure applied by the pressurizable or gravity-driven liquid reservoir310, yields the desired liquid flow rate. In one embodiment, the flowregulator 340 can provide two or more such fixed and predetermined flowrates with, for example, a rotatable disc that can be turned to selectand position one of a number of restricted passages, provided as holesthrough the disc, in alignment with the primary passage 322. Theselected restricted passage thus determines the flow rate through theregulator 340. In one such embodiment, the flow regulator can provideone relatively large fixed and predetermined flow rate, designated as a“prime” setting, which can be used to quickly prime the sheath 110 andthe rest of the system 100 with liquid before beginning a treatment of ahollow anatomical structure. This “prime” flow rate can be larger thanany of those specified herein for use when treating an HAS. The “prime”flow rate can be provided along with one or more “treatment” flow rates.

To use the liquid source 300, the practitioner can first connect thesource 300 to the sheath 100 via the outlet 332 and the sidearm 122 orother apparatus suitable to provide fluid communication between thesource 300 and the lumen of the sheath 110. Alternatively, theconnection can be made later in the process. The practitioner chargesthe liquid reservoir by setting the stopcock 326 to provide fluidcommunication only between the secondary passage 324 and the reservoir310, and connecting a syringe or other appropriate apparatus to the fillconnector 330. Notably, a syringe with a graduated barrel can beemployed to fill the reservoir 310 with a precise predetermined volumeof liquid. The syringe is operated to pump a desired volume (e.g. lessthan 100 cc, or less than 50 cc) of liquid through the plumbing network320 and into the reservoir 310. Where the reservoir 310 is of thepressurizable type, the inflow of liquid pressurizes the reservoir 310(e.g., by expanding the elastic bladder or forcing the piston backagainst the spring). Once the reservoir 310 is full, the practitionercan place the stopcock 326 in the closed position, preventing anyoutflow from the liquid source 300, and if desired remove the syringe orother apparatus from the fill connector 330. The sheath 110 can beprimed directly from the syringe, or with the liquid in the reservoir310, or from the syringe while still connected to the fill connector 330and with the stopcock 326 at a proper setting. Where suitable, the flowregulator 340 can be placed in the “prime” setting and the stopcock 326opened to allow liquid to flow from the reservoir 310 to the sheathlumen at the “prime” flow rate until the priming is complete, and thestopcock closed. However primed, the system 100 or sheath 110 isinserted into the target hollow anatomical structure as disclosedelsewhere herein. At the appropriate time after insertion, the stopcockis opened (and the flow regulator 340 set to the appropriate fixed andpredetermined flow rate) to deliver liquid from the reservoir 310 andinto the lumen of the sheath 110 at an appropriate fixed andpredetermined treatment flow rate as discussed herein, e.g., 5-60cc/hour, 5-40 cc/hour, 10-30 cc/hour, 15-25 cc/hour, or about 20cc/hour. The flow rate is then sustained, either at a constant rate orwithin a desirable range, for as long as necessary during the treatment.

Advantageously, the liquid source 300 and flow regulator 340 can beemployed to quickly and conveniently provide a liquid flow at a desiredflow rate for treating an HAS. In contrast, a conventional saline bagand tubing set can require a great deal of setup and adjustment beforethe desired flow rate is achieved. This increases the time and costexpended when performing a treatment.

FIGS. 4C and 4D depict one embodiment of the flow regulator 340 usablewith the liquid source 300. The flow regulator 340 of FIGS. 4C-4Dcomprises a reservoir chamber 342 having an inlet port 370, a dripchamber 346 having an outlet port 368, and a flow restriction 350. Theinlet port 370 is in fluid communication with the liquid reservoir 310(FIG. 4B) and supplies liquid to the reservoir chamber 342, which is influid communication with the drip chamber 346 via the flow restriction350. The flow restriction 350 regulates the flow rate of liquid into thedrip chamber 346. From the drip chamber 346, liquid is fed via theoutlet port 368 to the sidearm 122 (FIG. 4A) of the system 100 via, forexample, a length of tubing (not shown) interconnecting the flowregulator 340 and the sidearm 122. Thus the flow regulator 340, tubingand sidearm 122 can form a flow path between the liquid reservoir 310and the sheath lumen 116. The flow regulator 340 can be fabricated frommultiple injection-molded pieces which are joined or fixed together toform the illustrated flow regulator 340. At least the drip chamber 346can be formed from a transparent material so that a user may visuallyconfirm the presence of saline in the drip chamber 346.

The reservoir chamber 342 defines an internal lumen 344 that is in fluidcommunication with an internal lumen 348 defined by the drip chamber346. The inlet port 370 can comprise a spike 372 that can be directlycoupled to a liquid reservoir 310 (FIG. 4B) such as a saline bag. Thespike 372 defines an internal channel 374 forming a flow passage forliquid between the liquid reservoir 310 and the lumen 344. Othersuitable connectors, such as luer fittings, can be used in place of thespike 372 in other embodiments.

The flow restriction 350 can be configured to provide a fixed andpredetermined liquid flow rate at a desired flow rate for treating anHAS. The flow restriction 350 can comprise a restricted passage with anorifice having a predetermined effective opening that is sized toprovide the desired liquid flow rate. As illustrated, the flowrestriction 350 comprises a channel 352 having an inlet orifice 354 andan outlet orifice 356 and defining a flow passage 358 between the lumens344, 348. The flow passage 358 can be sized to provide an appropriatefixed and predetermined treatment flow rate as discussed herein, e.g.,5-60 cc/hour, 5-40 cc/hour, 10-30 cc/hour, 15-25 cc/hour, or about 20cc/hour. For example, the cross-sectional area of the flow path throughthe flow regulator 340 can decrease from that of the lumen 344 to thatof the flow passage 358 to provide a desired treatment flow rate. Theflow passage 358 through the channel 352 can have a fixed size.Optionally, the outlet orifice 356 can have a diameter of approximately0.5 mm. In another variation, the channel 352 can be a rigid member suchas a rigid tube or a rigid (e.g. glass) capillary tube.

The flow restriction 350 can further comprise a flow restrictor member360 positioned in the channel 352 to provide an appropriate fixed andpredetermined treatment flow rate as discussed herein, e.g., 5-60cc/hour, 5-40 cc/hour, 10-30 cc/hour, 15-25 cc/hour, or about 20cc/hour. As illustrated, the flow restrictor member 360 can comprise achannel restrictor 362 inserted into the inlet orifice 354 of thechannel 352 and extending at least partially into the flow passage 358.The channel 352 and channel restrictor 362 can be sized to provide a gaptherebetween for the passage of fluid. The gap can be on the order of0.025 mm. The gap can form an annulus extending around the channelrestrictor 362 and bordered by the channel. Optionally the annulus caninclude an annular gap between the channel restrictor 362 and thechannel 352 of approximately 0.025 mm.

The channel restrictor 362 can comprise a first portion 364 that isinserted into the flow passage 358 and a second portion 366 that is bentwith respect to the first portion 364 to hold the restrictor 362 inplace in the flow passage 358. The length of the first portion 364, i.e.how far the channel restrictor 362 protrudes into the flow passage 358,can be selected to control the flow rate. As a general rule, increasingthe length of the first portion 364 will decrease the flow rate. Thecross-sectional size of the first portion 364 can also affect the flowrate. Thus, both the cross-sectional size and length of the firstportion 364 of the channel restrictor 362 may be used to control theflow rate through the flow passage. Optionally, the channel restrictor362 can comprise a wire that is bent to form the first portion 364 andsecond portion 366. The first portion 364 can itself be slightly bent toimpart a springlike characteristic to the first portion that helps toretain the restrictor 362 in the flow passage 358.

FIGS. 4E-F depict an alternate embodiment of the flow regulator 340,which can be similar in structure, use and function to the flowregulator 340 of FIGS. 4C-D, except as further described herein. In theflow regulator 340 of FIGS. 4E-F, a bypass chamber 376 is provided forselectively bypassing the flow restriction 350. The bypass chamber 376defines a bypass channel 378 that fluidly communicates with the lumen344 of the reservoir chamber 342 via an inlet orifice 380 and with thelumen 348 of the drip chamber 346 via an outlet orifice 382.

By bypassing the flow restriction 350 using the bypass chamber 376, ahigher flow rate can be provided than that used during delivery ofenergy to a HAS to flush out the system 100. Flushing the system 100 maybe done before a treatment procedure to rid the system 100 of any airbubbles by filling the system 100 with fluid or during a treatmentprocedure to remove a blockage from the system 100.

A bypass controller 384 can be provided that selectively opens one ofthe orifices 380, 382 to allow fluid flow through the bypass channel 378to flush the system 100. As illustrated in FIG. 4F, the bypasscontroller 384 selectively opens that orifice 380 to allow fluid fromthe reservoir chamber to enter the bypass chamber 376 and pass throughthe open outlet orifice 382 and into the drip chamber 346. The bypasscontroller 384 can comprise a spring-biased valve 386 having a valvestem 388 with a push button head 390 at one end and a closure element392 spaced from the push button head 390. The valve 386 is biased to aclosed position, shown in FIG. 4E, in which the closure element 392 isseated against the orifice 380 and prevents fluid flow into the bypasschannel 378, by a spring 394 positioned between the closure element 392and the channel 352. The valve 386 can be moved to an open position,shown in FIG. 4F, in which the closure element 392 is spaced from theorifice 380, permitting fluid flow into the bypass channel 378, bydepressing the push button head 390. A sealing element 396 can be placedbetween the valve stem 388 and the exterior wall of the bypass chamber376 to prevent fluid leakage.

In a variation of the embodiment of FIGS. 4C and 4D, the channel 352 cancomprise a capillary tube that utilizes capillary action to pass liquidthrough the channel 352. The channel 352 comprising a capillary tube canbe sized to provide an appropriate fixed and predetermined treatmentflow rate with or without the need for the flow restrictor member 360.

FIGS. 5-7B depict another embodiment of the system 100, which can besimilar in structure, use and function to any of the variations of thesystems 100 of FIGS. 1-4, except as further described herein. In thesystem 100 of FIG. 5, the distal tip portion 114 of the shaft 112 of thesheath 110 comprises a number of radially expanded or expandable members115. The expandable members 115 preferably comprise strips of anappropriate metallic or polymeric material having a springlike biastoward a radially expanded configuration. When the expandable members115 are in the expanded configuration (FIGS. 5-7A), the members 115surround and are radially spaced from the emitting tip 162 of theoptical fiber 152 (or other light delivery device). The tip 162 ispreferably spaced proximally from the distal end of the expandablemembers 115 by a distance X of 2 mm to 20 mm. The fiber tip 162 cantherefore remain disposed within the set of expandable members 115during treatment, and the expandable members 115 can protect the hotfiber tip 162 from contact with the inner wall of the vein or othertarget HAS (and vice versa).

As can be seen from FIGS. 6 and 7B, the members 115 are preferablyretractable into the shaft 112 by drawing an inner tube assembly 180proximally into a surrounding outer tube 182. The outer tube 182 forcesthe members 115 radially inward as the inner tube assembly 180 is drawninto the lumen of the outer tube 182. As depicted, the inner tubeassembly 180 can comprise an inner tube 184, and the expandable members115, which are preferably attached to the distal end of the inner tube184. The inner tube 184 receives the optical fiber 152 or other lightdelivery device within its inner lumen, in a manner similar to the lumen116 of the shaft 112 shown in FIGS. 1-4. Preferably, the lumen of theinner tube 184 is sized to accommodate a space for liquid flow betweenthe inner tube 184 and the fiber 152, to facilitate optional delivery ofliquid during treatment with the system 100 of FIGS. 5-7B, as describedabove in connection with the embodiments of FIGS. 1-4.

The system 100 of FIGS. 5-7B can be used in a manner generally similarto the systems 100 of FIGS. 1-4, except as follows. With the expandablemembers 115 in the retracted configuration as shown in FIG. 7B, thesheath 110 can be delivered over a guidewire (or otherwise) to thedesired treatment location. Once the sheath 110 is in position, theguidewire can be withdrawn and the members 115 can be expanded by movingthe outer and inner tubes 182, 184 relative to each other such that themembers 115 move distally beyond the end of the outer tube 182. Free ofthe constraint of the outer tube 182, the members 115 then self-expandto the expanded configuration shown in FIGS. 5-7A. The optical fiber 152or other light delivery device can then be advanced through the hub 120and down the shaft 112 and positioned so that the tip 162 is disposedwithin the members 115, and spaced proximally by the distance X from thedistal ends of the members 115. As discussed above, the fiber 152 caninclude a mark (or a projection such as a flange, slidable collar or“donut”) appropriately spaced from the tip 162 to indicate properpositioning of the tip 162 relative to the expanded members 115 uponalignment of the mark with a reference point such as the proximal edgeof the hub 120.

Once the tip 162 is in position, the treatment can proceed as discussedelsewhere herein. After completion of the treatment, the members 115 canbe retracted by drawing the inner tube assembly 180 into the outer tube182. The system 100 can then be withdrawn from the patient in the usualmanner.

FIGS. 8A-8B depict the distal portion of an alternative embodiment of asheath 110 for use with the system 100. The sheath 110 of FIG. 8includes an expandable collar 190 which is expandable via compressioncreated by interaction of an outer tube 192 and an inner tube 194. Thetubes 192, 194 are slidable relative to each other so that the collar190 can be compressed (FIG. 8B) between the distal end of the outer tube192 and a flange 196 fixed to the distal end of the inner tube 194. Theoptical fiber 152 or other light delivery device can be received in aninner lumen of the inner tube 194. Preferably, during use, the collar190 is in the expanded configuration and the light emitting tip 162 ofthe fiber 152 is positioned close to (e.g., about 2 mm to 20 mm proximalof) a distal opening 198 of the inner tube 194. The expanded collar 190prevents contact between the hot fiber tip and the HAS wall duringtreatment. If desired, a liquid flow can be provided via the inner lumenof the inner tube 194 (around the fiber 152) during application oflight/laser energy, as discussed elsewhere herein. In variousembodiments, the expandable collar 190 can comprise a fluid filledannular balloon, or an annular, solid member formed from a compliant andcompressible polymer material, or the like.

FIGS. 9A-9B depict another embodiment of a sheath 110 which can besimilar in structure, function and use to the sheath 110 of FIGS. 8A-8B,except for the use of an expandable coil 191 in place of the expandablecollar 190. The coil 191 can alternatively comprise a preshaped memorycoil which can be deployed by a technique other than the compressiondepicted in FIGS. 9A-9B, such as by retraction of an overlying sheath,or a coil formed from power-induced or resistive-heating-induced memorymaterial such as Nitinol or compatible materials, to facilitateexpansion of the coil to its “remembered” expanded configuration bypassing an electrical current through the coil through electrical leads(not shown) connected thereto.

FIGS. 10A-10B depict another embodiment of a sheath 110 which can besimilar in structure, function and use to the sheath 110 of FIGS. 8A-8B,except that the expandable collar 190 is a balloon which is inflatableand deflatable via one or more inflation passages (not shown) disposedin the outer tube 192. In this embodiment, the outer tube 192 and innertube 194 are preferably not movable relative to each other. In anotherembodiment, the collar 190 is a mass of compliant, hydrophilic material(e.g. a sponge) that can be expanded by supplying a fluid to it fromconduit(s) formed in the sheath 110.

FIG. 11 depicts another embodiment of the system 100 which can besimilar in structure, function and use to the systems 100 shown in FIGS.1-4, except as further discussed below. In this embodiment, the distaltip portion 114 of the sheath 110 contains one or more holes 199 in itssidewall. Where employed, the holes 199 communicate hot or boilingliquid outward to the HAS at location(s) along the length of the sheathtip 114. The holes 199 can be arranged in one or more circumferentialbands as depicted. The size of the holes 199, the number of holes ineach band, the number of bands, and the position of the bands relativeto the distal end of the sheath tip 114 can be varied to control thelength of the treatment zone. The holes 199 provide a pressure relief ofthe hot and/or boiling liquid inside the sheath 110, to reduce thepressure and velocity of the fluid ejected through the opening 174 inthe distal end of the tip portion 114 during treatment.

FIGS. 12A and 12B depict another embodiment of the system 100, which canbe similar in structure, function, and use to the systems 100 shown inFIGS. 1-3, except as further discussed below. In this embodiment, thedistal tip portion 114 of the shaft 112 preferably has a generallyconstant inner and outer diameter and is transparent to, or otherwisehighly transmissive of, the wavelength of light emitted via the fibertip 162. The fiber tip 162 includes a shaped surface 200 having at leastone face or portion oriented non-perpendicularly to the longitudinalaxis A of the optical fiber 152. The shaped surface 200 can beconfigured in accordance with a desired light dispersion pattern. Forexample, angle refraction physics and/or other scientific principlesgoverning light behavior can be employed to determine a desiredconfiguration for the shaped surface 200 and, thereby, control theemission of light from the light delivery device 150 to the HAS walls,the sheath distal tip portion 114, and/or delivered liquid.

In the illustrated embodiment, the shaped surface 200 has a generallyconical configuration that terminates at a point coincident with thedistal end of the optical fiber 152. The fiber tip 172 with the conicalshaped surface 200 provides for more radial dispersion of the light ascompared to, for example, a blunt end fiber tip 162, such as the fibertip 162 shown in FIG. 3. In other words, more of the light is directedradially toward the adjacent HAS walls rather than axially into thelumen of the HAS located distally of the system 100. Otherconfigurations are within the scope of the present disclosure. Forexample, the angled surface 200 can have a generally conicalconfiguration that terminates proximally of the most distal end of theoptical fiber 152 such that the fiber tip 162 terminates at a bluntsurface orthogonal to the longitudinal axis of the optical fiber 152 andhaving a transverse sectional area less than that of portion of the core156 covered by the jacket 160, which can sometimes be referred to as afrustoconical configuration. Other contemplated configurations includepyramidal, prismatic, and spherical surfaces.

Factors to consider when determining the configuration of the shapedsurface 200 include the configuration and material of the distal tipportion 114 of the sheath 110. In some variations of this embodiment,the shape and material of the distal tip portion 114 can affect the pathof the light emitted from the fiber tip 162. Conversely, theconfiguration and material of the distal tip portion 114 can be selectedbased on a predetermined configuration of the shaped surface 200. Theshape and material of the distal tip portion 114 shown in FIGS. 12A and12B are provided for illustrative purposes and are not intended to limitthe present disclosure. The optical fiber 152 with the tip 162 havingthe shaped surface 200 can be utilized with any suitable sheath 110,including any of the sheaths 110 in the embodiments of FIGS. 1-11.

FIGS. 13-16 depict other embodiments of the system 100, which can besimilar in structure, function, and use to the systems 100 shown inFIGS. 1-3, except as further discussed below. Each of the embodiments ofFIGS. 13-16 can comprise a distally closed sheath 110 as depicted;differences between each of the embodiments of FIGS. 13-16 and FIGS. 1-3are described below.

In the embodiment of FIG. 13, a plug 210 located at the open distal end172 of the distal tip portion 114 effectively closes the distal end ofthe sheath 110. The distal tip portion 114 is transparent to, orotherwise highly transmissive of, the wavelength(s) of light emitted viathe fiber tip 162, while the plug 210 is substantially not transmissiveor substantially opaque to the wavelength(s) of light. Any suitablematerial or combination of materials can constitute the plug 210, andone suitable material for the plug 210 is a metal.

The plug 210 includes a reflective body 214 extending proximally towardand aligned with the direction of light emission from the fiber tip 162.The reflective body 214 reflects the light emitted from the fiber tip162 and disperses the light radially outward toward the HAS walls.Additionally, the reflective body 214 effectively disperses or spreadsthe light beam, thereby decreasing the flux density of the lightrelative to that of the light as it exits the fiber tip 162, which cancontribute to minimizing blood boiling effects and coagulation problems,such as deep vein thrombosis. The reflective body 214 can be configuredto reflect the light radially, radially and proximally, and/or radiallyand distally. In the illustrated embodiment, the reflective body 214 hasa generally conical configuration, which provides 360-degree radial andradial/proximal reflection of the light from the fiber tip 162. Theshape of the reflective body 214 shown in FIG. 13 is provided as anexample; other configurations of the reflective body 214 are within thescope of the invention. Other examples of the reflective body 214include, but are not limited to, pyramidal, prismatic, and spherical orhemispherical bodies. Further, the surface of the reflective body 214can be treated, such as by polishing or coating, to provide a surfacetexture having a desired reflectivity.

In the illustrated embodiment, the plug 210 and the distal end 172 ofthe distal tip portion 114 both have a curved distal surface 216, 218that together form a rounded distal end of the sheath. The roundedconfiguration facilitates insertion of the system 100 into a guidesheath or into the HAS.

The system 100 of FIG. 13 can employ any suitable light delivery deviceand is not limited to the light delivery device with the optical fiber152 having the blunt fiber tip 162. For example, the system 100 canalternatively use the optical fiber 152 of FIGS. 12A and 12B having thefiber tip 162 with the shaped surface 200, which can further contributeto dispersion of the light beam. Other optical fibers 152 described andnot described in this application can be used with the system 100 ofFIG. 13.

In a variation of the embodiment of the system 100 of FIG. 13, thesheath 110 can include one or more ports, such as a port formed in thedistal tip portion 114, for fluidly communicating the fluid deliveryspace 178 with the HAS lumen to render the system 100 suitable for fluiddelivery into the HAS lumen. One or more such ports can additionally oralternatively be located in the plug 210.

In another variation, the plug 210 or a portion thereof can be formed ofa material at least partially transmissive of the wavelength of lightemitted via the fiber tip 162 such that a portion of the light reflectsfrom the reflective body 214 and a portion transmits through the plug210. For example, the reflective body 214 can be made opaque while therest of the plug 210 can be made transmissive.

In yet another variation of the embodiment of the system 100 of FIG. 13,one or both of the plug 210 and the distal tip portion 114 can beremovable from the shaft 112. Optionally, the plug 210 and/or the distaltip portion 114 can be modular or replaceable with other types of plug210 and distal tip portion 114. The removable and replaceable featuresof the distal tip portion 114 and structures associated therewith can beapplied to any of the embodiments of the system 100 described in thisapplication.

In the embodiment of the system 100 in FIG. 14A, the distal tip portion114 of the sheath 110 comprises a cylindrical region 220 terminating ata rounded distal end 222 that distally closes the sheath 110. The distaltip portion 114 is transparent to, or otherwise highly transmissive of,the wavelength(s) of light emitted via the fiber tip 162, except thatthe rounded distal end 222, or at least a portion of the rounded distalend 222, includes a light absorbing body 224 arranged within the path ofthe light emitted from the fiber tip 162. The light absorbing body 224prevents or at least inhibits transmission of light therethrough, andthe light absorbed by the body 224 heats the body 224, which in turnheats the HAS walls in contact with (and/or nearby) the body 224, asdescribed in more detail below. The light absorbing body 224 can haveany suitable form, such as a material deposited, coated, or otherwiseattached to the rounded distal end 222 and can be located on a proximaland/or a distal surface of the rounded distal end 222. In theillustrated embodiment, the light absorbing body 224 is provided on boththe proximal and distal surfaces of the rounded distal end 222. Thematerial of the light absorbing body 224 is highly absorbent of thewavelength of light emitted via the fiber tip 162 such that the lightheats the material. As a result of this configuration, light emittedfrom the fiber tip 162 can both be absorbed by the light absorbing body224 and transmit through other areas of the distal tip portion 114. Thelight absorbed by the light absorbing body 224 heats the light absorbingbody 224, which can thereby conductively heat the HAS walls in contactwith the light absorbing body 224 (and/or otherwise heat the nearby HASwalls). The light transmitted through the distal tip portion 114 canheat the HAS walls via light energy transmission directly to the HASwalls.

The fiber 152 and the distal tip portion 114 can have any suitablerelative size and positioning. As an example, a distance Y of theoptical fiber 152 between the jacket 160 and the fiber tip 162 can beabout 1-2 mm, the distance X between the fiber tip 162 and the mostdistal portion of the rounded distal end 222 can be about 3-5 mm, and adistance Z corresponding to the length of the distal tip portion 114 canbe about 5-10 mm.

The system 100 of FIG. 14A can employ any suitable light delivery deviceand is not limited to the light delivery device with the optical fiber152 having the blunt fiber tip 162. For example, the system 100 canalternatively use the optical fiber 152 of FIGS. 12A and 12B having thefiber tip 162 with the shaped surface 200. In such a variation, thelight absorbing body 224 can be adapted according to the direction oflight emission from the shaped surface 200 of the fiber tip 162. Forexample, a portion of the light absorbing body 224 can be extended tothe cylindrical region 220 of the distal tip portion 114. Other opticalfibers 152 described and not described in this application can be usedwith the system 100 of FIG. 14A.

In a variation of the embodiment of the system 100 of FIG. 14A, a lightscattering material located in the space 178 between the optical fiber152 and the distal tip portion 114, as illustrated in FIG. 14B, canfacilitate transmission of the light to the light absorbing body 224 andthrough the distal tip portion 114. The light scattering material can bea liquid, a solid, or combination of a liquid and a solid. For example,the light scattering material can be a translucent liquid with areflective solid particulate suspended in the liquid. For such a lightscattering material, the liquid transmits the light for reflection bythe solid particulate. The aggregate effect of the suspended particulateis to scatter the light incident on the scattering material from thefiber 152. This can include scattering the light radially, radially anddistally, or radially and proximally.

In another variation of the embodiment of the system 100 of FIG. 14A,the light absorbing body 224 can be a body separate from and closing thedistal tip portion 114, similar to the manner in which the plug 210closes the distal tip portion 114 in the embodiment of FIG. 13. Further,the light absorbing body 224 and the rounded distal end 222 need not berounded; other configurations, such as blunt and tapered, are within thescope of the invention.

In yet another variation of the embodiment of the system 100 of FIG.14A, the sheath 110 can include one or more ports, such as a port formedin a sidewall of the distal tip portion 114, for fluidly communicatingthe fluid delivery space 178 with the HAS lumen. One or more ports canadditionally or alternatively be located in the light absorbing body224.

In the embodiment of the system 100 in FIG. 15, the distal tip portion114 of the sheath 110 comprises the cylindrical region 220 terminatingat the rounded distal end 222 that distally closes the sheath 110,similar to the sheath 110 in the embodiment of the device 100 shown inFIG. 14A. The distal tip portion 114 of the sheath 110 in FIG. 15,however, lacks the light absorbing body 224 of FIG. 14A. Instead, theentire distal tip portion 114 can transmit the light emitted from thefiber tip 162. The cylindrical region 220 and the rounded distal end 222can be integrally formed, as illustrated, or formed of separate bodiesjoined in any suitable manner. In one variation, the rounded distal end222 can be formed as a separate body removably coupled to thecylindrical region 220.

The system 100 of FIG. 15 includes the light delivery device 150 havingthe shaped surface 200 at the fiber tip 162 shown in the embodiment ofFIGS. 12A and 12B and described above in detail. The system 100 of FIG.15, however, can employ any suitable light delivery device and is notlimited to the light delivery device with the optical fiber 152 havingthe fiber tip 162 with the shaped surface 200. For example, the system100 can alternatively use the optical fiber 152 having the blunt fibertip 162. Other optical fibers 152 described and not described in thisapplication can be used with the system 100 of FIG. 15.

As described above for variations of the embodiment of FIG. 14A,variations of the embodiment of the system 100 in FIG. 15 can includeother features, including a light scattering material in the space 178between the optical fiber 152 and the distal tip portion 114 and/or oneor more ports in the distal end or sidewall of the distal tip portion114. In another variation, the rounded distal end 222 can have aconfiguration other than rounded, as discussed below with respect to theembodiment of the system 100 in FIG. 16.

The embodiment of the system 100 in FIG. 16 can be similar to theembodiment of the system 100 in FIG. 15, except that the distal end 222has a generally conical configuration rather than a roundedconfiguration. The distal end 222 shown in FIG. 16 comprises a taperedregion 230 that terminates at a closed tip 232. The tapered region 230can be configured to transmit the light emitted from the fiber tip 162in a desired pattern. For example, the tapered region 230 can bedesigned to refract the light distally and radially, completelyradially, or proximally and radially. In the illustrated embodiment, theshape of the tapered region 230 effectively redirects the light emittedfrom the fiber tip 162 to provide more radial transmission of the lightto the adjacent HAS walls, as indicated by the radially oriented arrowsin FIG. 16, than would be present without the tapered region 230. Thetapered region 230 can have any suitable configuration, and, as oneexample and as illustrated, the tapered region 230 can be angleddifferently than the shaped surface 200 of the fiber tip 162. As anotherexample, the tapered region 230 can be angled at the same angle employedwith the shaped surface 200 of the fiber tip 162.

The system 100 of FIG. 16 includes one suitable manner of joining thedistal tip portion 114 and the shaft 112 of the sheath 110 differentfrom that shown in the previous embodiments. While the distal endportion 114 and the shaft 112 can be joined in any suitable manner, aheat shrinkable sleeve 240 joins the distal tip portion 114 and theshaft 112 of the system 100 illustrated in FIG. 16. An adhesive, such asan epoxy, can be employed independently or in combination with thesleeve 240 to facilitate joining the distal tip portion 114 and theshaft 112.

The system 100 of FIG. 16 includes the light delivery device 150 havingthe shaped surface 200 at the fiber tip 162 shown in the embodiment ofFIGS. 12A and 12B and described above in detail. The system 100 of FIG.16, however, can employ any suitable light delivery device and is notlimited to the light delivery device with the optical fiber 152 havingthe fiber tip 162 with the shaped surface 200. For example, the system100 can alternatively use the optical fiber 152 having the blunt fibertip 162. Other optical fibers 152 described and not described in thisapplication can be used with the system 100 of FIG. 16.

In a variation of the embodiment of the system 100 of FIG. 16, the tip232 of the tapered region 230 can be opened rather than closed. Theopened tip 232 can facilitate delivery of fluid from the fluid deliveryspace 178 while still redirecting the light emitted from the fiber tip162 and preventing contact of the fiber tip 162 with the HAS walls. Asan alternative or addition, the distal tip portion 114 can include oneor more fluid ports in the distal end or sidewall of the tip portion114, as described above with respect to other embodiments. In anothervariation of the system 100 of FIG. 16, the system 100 can include alight scattering material in the space 178 between the optical fiber 152and the distal tip portion 114, as described above for the embodiment ofFIG. 14A.

FIGS. 17A-20B depict other embodiments of the light delivery device 150,which can be similar in structure, function, and use to the lightdelivery devices 150 shown in FIGS. 1-16, except as further discussedbelow.

The light delivery device 150 of FIGS. 17A and 17B can be similar to thelight delivery device 150 in the embodiment of FIGS. 12A and 12B, exceptthat the light delivery device 150 of FIGS. 17A and 17B includes a lumen250 formed in the optical core 156 of the optical fiber 152 andterminating at a distal opening 252 at the fiber tip 162. While thelumen 250 can have any suitable size and cross-sectional shape, in oneexample, the optical fiber 152 can have an outer diameter in a range ofabout 300-1000 μm, and the lumen 250 can have a circular cross-sectionwith an inner diameter in a range of about 300-600 μm. Further, thefiber tip 162 of the light delivery device 150 can include any desiredconfiguration for the shaped surface 200 and is not limited to thegenerally conical shape shown in FIGS. 17A and 17B. For example, thefiber tip 162 can be prismatic, rounded, etc., according to a desiredlight emission pattern. Alternatively, the fiber tip 162 can be blunt.

In one variation of the embodiment, the lumen 250 can be fluidly coupledto the sidearm 122 (FIG. 1) or other fluid source such that fluidsupplied to the lumen 250 via the fluid source flows through the lumen250 and exits the lumen 250 at the distal opening 252 for delivery tothe HAS. Internal reflection of the light in the lumen 250 can heat thefluid as it flows through the lumen 250.

In another variation of the light delivery device 150 of FIGS. 17A and17B, the internal surface of the optical core 156 forming the lumen 250can be coated with a material to prevent internal reflection of thelight in the lumen 250. Such a coating can be beneficial when using thelumen 250 for fluid delivery if heating of the fluid is not desired.

The light delivery device 150 of FIGS. 17A and 17B can be employed withany suitable sheath, including any of the sheaths 110 shown with respectto the embodiments of FIGS. 1-16 and other sheaths not illustrated ordescribed in this application, and used in a manner generally similar tothat described above for the system 100 of FIGS. 1-3.

Embodiments of the light delivery device 150 illustrated in FIGS. 18-20Bcan be employed without a sheath to treat an HAS as described elsewhereherein. These embodiments are designed to prevent direct contact betweenthe HAS walls and the fiber tip 162. Each of these embodiments,particularly the differences between them and the embodiments of thelight delivery devices 150 previously presented are described below.

The embodiment of the light delivery device 150 shown in FIG. 18 can besimilar to the light delivery device 150 of the embodiment in FIGS. 1-3,except that the light delivery device 150 of FIG. 18 includes a distaltip portion 260 extending from the jacket 260 to a distal end 262projecting beyond the fiber tip 162 a predetermined distance. The distaltip portion 260, similar to the distal tip portion 114 of the shaft 112in previous embodiments, is transparent to, or otherwise highlytransmissive of, the wavelength of light emitted via the fiber tip 162.Extension of the distal end 262 beyond the fiber tip 162 preventscontact between the HAS walls and the fiber tip 162. The distal end 262can be blunt, as illustrated, or otherwise configured for a desiredlight emission pattern. The distal tip portion 260 can be coupled to thejacket 160 in any suitable manner, such as by a heat shrinkable sleeve264 optionally combined with an adhesive, including epoxy adhesives.

The embodiment of the light delivery device 150 in FIG. 19 provides anexample of modifying the distal end 262 of the distal tip portion 260.The light delivery device 150 of FIG. 19 can be otherwise similar tothat of FIG. 18. The distal end 262 shown in FIG. 19 has a roundedconfiguration and includes an annular projection 266 extending radiallyinward distally of the fiber tip 162. The projection 266 inhibitsinadvertent distal movement of the optical core 156 and the cladding 158relative to the jacket 160 and the distal tip portion 260 beyond theposition shown in FIG. 19, and the rounded configuration facilitatessmooth insertion of the light delivery device into the HAS. While therounded configuration can provide such a benefit, it is within the scopeof the present disclosure for the distal end 262 and/or the projection266 to be shaped otherwise.

Referring now to FIGS. 20A and 20B, another embodiment of the lightdelivery device 150 comprises the optical fiber 152 having the opticalcore 156, the cladding 158, and the jacket 160 as described above forthe other embodiments of the light delivery device 150 and furtherincludes a distal body 270 enclosing a distal portion of the opticalfiber 152 including at least the fiber tip 162. In the illustratedembodiment, the distal body 270 encloses the portion of the optical core156 not covered by the cladding 158 and the jacket 160. In a variation,the cladding 158 can extend along the portion of the optical core 156enclosed by the distal body 270, except for the fiber tip 162. Thedistal body 270 can assume any suitable shape and is shown by way ofexample as having a tubular configuration with a rounded distal end 272.

The distal body 270 prevents direct contact between the fiber tip 162and the HAS walls and can be transparent to, highly transmissive of, orabsorbing of the wavelength of light emitted from the fiber tip 162. Inone variation, the distal body 270 can contain a material, such as afluid, a solid, or a combination fluid and solid, that absorbs thewavelength of light emitted by the fiber tip 162 such that the lightenergy heats the distal body 270. The heated distal body 270conductively heats the HAS walls when in contact therewith.Alternatively or additionally, the heated distal body 270 can heat fluidin the HAS lumen, including fluid delivered by the system 100. Inanother variation, the distal body 270 can contain a material, such as afluid, a solid, or a combination fluid and solid, at least partiallytransmissive of the light emitted from the fiber tip 162 such that thelight travels through the distal body 270 to the HAS walls, therebyheating the HAS walls via light energy transmission. Optionally, thematerial can include reflective/scattering particles to facilitate inthe dispersion of light to the HAS walls.

As stated above, the light delivery devices 150 of FIGS. 18-20B can beemployed without a sheath. Each of these embodiments can include anelement that precludes direct contact between the HAS walls and thefiber tip 162. For the embodiments of FIGS. 18 and 19, the projection ofthe distal end 262 beyond the fiber tip 162 inhibits contact between theHAS walls and the fiber tip 162. In the embodiment of FIGS. 20A and 20B,the distal body 270 provides a physical barrier between the HAS wallsand the fiber tip 162. The manner of using the light delivery devices150 of these embodiments without a sheath is substantially the same asdescribed above for the embodiments of FIGS. 1-3, except that theprocess can be adapted slightly to accommodate the absence of thesheath. For example, a guide sheath can be inserted along the guide wirefor purposes of introducing the light delivery device 150 and thenwithdrawn once the light delivery device 150 is situated in the HAS.Alternatively, the light delivery device 150 can be adapted forinsertion along the guide wire such that a guide sheath or similarelement is not needed. As still another alternative, the light deliverydevices 150 of FIGS. 18-20B can be employed to treat an HAS (such as avein) as described elsewhere herein, but without use of a guidewire or asheath.

Alternatively, the embodiments of the light delivery devices 150 inFIGS. 18-20B can be used with a sheath, including the sheaths 110 shownwith respect to the embodiments of FIGS. 1-16 and other sheaths notillustrated or described in this application. In such a case, thesystems 100 with the light delivery device 150 of any of FIGS. 18-20Bcan be used in a manner generally similar to that described above forthe system 100 of FIGS. 1-3.

FIGS. 21A-28 depict an alternative embodiment of the system 100, whichcan be similar in structure, use and function to the systems 100 shownin FIGS. 1-4A and 11-16, except as further discussed below. For each ofthe embodiments of FIGS. 21A-28, the system 100 is provided with aposition limiter 400 which is configured to limit the position of thefiber tip 162 to a predetermined position suitable for emitting lightfrom the optical fiber 152, which can also be termed a firing position.The firing position can comprise a position proximal of the distal end172 of the distal tip portion 114. The position limiter 400 can beconfigured to assist the user in placing the fiber tip in the firingposition by spacing the fiber tip 162 from the distal end 172 by thedistance X of 2 mm to 20 mm, 2 mm to 10 mm, 2 mm to 8 mm, 2 mm to 5 mm,2 mm to 4 mm, or 3 mm; or otherwise by a distance suitable to minimize,inhibit, or substantially prevent buildup of proteins, coagulum and/orcarbonization on the fiber tip 162. The spacing can also be suitable tominimize, inhibit, or substantially prevent perforation of the HAS beingtreated (including veins in particular). The position limiter 400 isadvantageous when the optical fiber 152 is inserted into the sheath 110after the sheath 100 has been positioned in a HAS because the positionlimiter 400 provides tactile feedback to a user who is not able tovisually determine when the fiber tip 162 reaches the firing positionand further prevents the fiber tip 162 from being advanced distallybeyond the firing position and into the HAS.

The position limiter 400 can be located anywhere along the length of theoptical fiber 152 or the introducer sheath 110. It can be beneficial toplace the position limiter nearer the fiber tip 162 or the distal tipportion 114, respectively, than the proximal end of either. Thus thedistance between the position limiter 400 and the fiber tip 162 isminimized, which facilitates manufacture by minimizing the dimensionrequiring control during assembly of the position limiter to the fiber.With a smaller distance between the position limiter 400 and the fibertip 162, that distance can be manufactured to a greater degree ofprecision and with less expense.

As illustrated, the position limiter 400 can comprise a stop configuredto limit the relative movement of the optical fiber 152 within the lumen116 when the fiber tip 162 is at the firing position or distance X. Thestop can comprise cooperating structures on the optical fiber 152 andthe sheath 110 that are configured to prevent the insertion or distalmovement of the distal tip of the optical fiber 152 into the lumen 116beyond the firing position. As illustrated, the cooperating structure onthe optical fiber 152 can include a tube 402 or other protrusion atleast partially surrounding the jacket 160 of the optical fiber 152 andhaving a fixed position relative to the fiber tip 162. The cooperatingstructure on the sheath 110 can include a shoulder 404 formed in aportion of the shaft 112 by inserting a distal end of the shaft 112 intothe distal tip portion 114 to create a narrowed portion of the lumen 116which tapers in the distal direction toward the distal tip portion 114.The outer diameter of the shaft 112 proximal of the shoulder 404 can beapproximately equal to the outer diameter of the distal tip portion 114,which can optionally be approximately 1.75 mm. The wall of the shaft 112can optionally be approximately 0.005 mm thick.

In the embodiment of FIGS. 21A and 21B, the tube 402 comprises anopen-ended hollow cylinder having an annular sidewall 405 with a distalface 406, a proximal face 408, and a channel 410 extending between thedistal and proximal faces 406, 408. The tube 402 is mounted to theoptical fiber 152 with the optical fiber 152 extending through thechannel 410 and the fiber tip 162 spaced a predetermined distance fromthe distal face 406 selected such that upon insertion of the opticalfiber 152 into the lumen 116, the distal face 406 will cooperate withthe shoulder 404 to prevent movement of the fiber tip 162 beyond thepredetermined firing position. The distal face 406 can optionally belocated within 10-20 mm of the fiber tip 162, or 12 mm from the fibertip 162.

In the embodiment of FIGS. 22A-22C, the tube 402 comprises an open-endedhollow cylinder similar to the tube 402 of FIGS. 21A and 21B, with theexception that the sidewall 405 comprises one or more recesses 412formed adjacent the distal face 406. The recesses 412 provide flowpassages that permit the passage of liquid from a liquid source, forexample, liquid source 300 (FIGS. 4A and 4B) distally past the junctionof the cooperating structures 402, 404 and into the fluid delivery space178. The size of the recesses 412 can be selected to provide a fixed andpredetermined liquid flow rate so that the tube 402 (or the cooperatingstructures 402, 404) function(s) as a liquid flow regulator in additionto a position limiter or stop. In this case, the flow rate of fluid tothe fluid delivery space 178 can be controlled without the need for oruse of a flow regulator (FIGS. 4B-4F) upstream of the sheath 112.

In the embodiment of FIGS. 23A and 23B, the tube 402 comprises anopen-ended hollow cylinder similar to the tube 402 of FIGS. 21A and 21B,with the exception that the tube 402 is fabricated from a porousmaterial providing pores 416 through the tube 402 through which theliquid can flow. The pore size can be selected to provide a fixed andpredetermined liquid flow rate through the tube walls so that the poroustube 402 can function as both a liquid flow regulator and a positionlimiter or stop. In this case, the flow rate of fluid to the fluiddelivery space 178 can be controlled without the use of or need for aflow regulator 340 (FIGS. 4B-4F) upstream of the sheath 112. Suitableporous materials include ceramics and polymers such as UHMWPE, HDPE,LDPE, PP, PC, EVA, PVDF, and TPU. With this configuration, the fluid mayenter the sidewall 405 or proximal face 408 and pass through the pores416 to exit through the distal face 406. This configuration does notrequire the discrete flow paths through or around the tube 402 as foundin the embodiment of FIGS. 22A-22C.

In the embodiment of FIGS. 24A and 24B, the tube 402 is similar to theporous tube 402 of FIGS. 23A and 23B, with the exception that thesidewall 405 comprises a distal conical section 418 tapering toward thedistal face 406 and a proximal conical section 420 tapering toward theproximal face 408. The taper of the distal conical section 418 can begenerally complementary to the taper of the shoulder 404, asillustrated, so that the distal conical section 418 will match theshoulder 404 when the fiber tip 162 is in the predetermined firingposition. With this configuration, the fluid may enter the sidewall 405,proximal face 408, or proximal conical section 420 and pass through thepores 416 to exit through the distal face 406. Alternately, if the taperof the distal conical section 418 is not complementary to the taper ofthe should 404, fluid may also exit through the distal conical section418. Either configuration does not require the discrete flow pathsthrough or around the tube 402 as found in the embodiment of FIGS.22A-22C. The tube 402 can optionally be approximately 5 mm long, with anouter diameter of 1.2 mm. The channel 410 can optionally have an innerdiameter of 0.8 mm.

In the embodiment of FIGS. 25A-25D, the tube 402 comprises an open-endedhollow cylinder similar to the tube 402 of FIGS. 21A and 21B, with theexception that the tube 402 comprises two angled faces 422 cut throughthe distal face 406 and the sidewall 405 at an angle with respect to thelongitudinal axis A of the optical fiber 152. The angled faces 422 formtwo spaces 424 that permit the passage of liquid from a liquid source,for example, liquid source 300 (FIGS. 4A and 4B) between the angledfaces 422 distally past the junction of the cooperating structures 402,404 and into the fluid delivery space 178. The size of the spaces 424can be selected to provide a fixed and predetermined flow rate so thatthe tube 402 (or the cooperating structures 402, 404) can function asboth a liquid flow regulator and a position limiter or stop. In thiscase, the flow rate of fluid to the fluid delivery space 178 can becontrolled without the need for or use of a flow regulator (FIGS. 4B-4F)upstream of the sheath 110. The size of the spaces 424 can be selectedby changing the angle of the angled faces 422 with respect to thelongitudinal axis A. The tube 402 can optionally have an outer diameterof 1.2 mm and an inner diameter of 0.85 mm. The angled face 422 canoptionally extend approximately 3 mm proximally from the distal face 406and be formed at an angle of 30-45 degrees to the longitudinal axis A.

In the embodiment of FIGS. 26A-26D, the tube 402 comprises an open-endedhollow cylinder similar to the tube 402 of FIGS. 21A and 21B, with theexception that the distal face 406 formed at an angle with respect tothe longitudinal axis A of the optical fiber 152. The angled distal face406 comprises a distal-most tip 414 that will cooperate with theshoulder 404 to prevent movement of the fiber tip 162 beyond thepredetermined firing position. The angled distal face 406 recedesproximally from the distal-most tip 414 to provide a space between theangled distal face 406 and the shoulder 404 that permits the passage ofliquid from a liquid source, for example, liquid source 300 (FIGS. 4Aand 4B) into the fluid delivery space 178. The tube 402 can optionallyhave an outer diameter of 1.2 mm and an inner diameter of 0.85 mm. Theangled distal face 406 can optionally extend approximately 3 mm alongthe longitudinally axis A and be formed at an angle of 20-45 degrees tothe longitudinal axis A.

While the embodiments of FIGS. 21A-26D illustrate various positionlimiters 400 comprising tubes 402 cooperating with a portion of theshaft 112 to limit the position of the fiber tip 162, it is alsounderstood that the distal tip portion 114 can be configured tocooperate with the tubes 402 of FIGS. 21A-26D to limit the position ofthe fiber tip 162. In the embodiment of FIG. 27, the cooperatingstructure on the optical fiber 152 comprises the open-ended tube 402 ofFIGS. 21A and 21B, although any of the tubes 402 shown herein could beused, and the cooperating structure on the sheath 110 comprises ashoulder 426 formed in the distal tip portion 114 that creates anarrowed portion of the lumen 116 which tapers in the distal directiontoward the distal end 172. The distal face 406 of the tube 402 willcooperate with the shoulder 426 to prevent movement of the fiber tip 162beyond the predetermined firing position.

In the embodiment of FIG. 28, the cooperating structure on the opticalfiber 152 comprises the open-ended tube 402 of FIGS. 21A and 21B,although any of the tubes 402 shown herein could be used, and thecooperating structure on the sheath 100 comprises a proximal face 428 ofthe distal tip portion 114. The distal face 406 of the tube 402 willcooperate with the proximal face 428 of the distal tip portion 114 toprevent movement of the fiber tip 162 beyond the predetermined firingposition.

Additional embodiments comprise methods of sterilization. Certain suchmethods can comprise sterilizing, either terminally or sub-terminally,any of the apparatus disclosed herein that are intended for insertioninto (or other contact with) the patient or that are intended for use ator near the surgical field during treatment of a patient. Any suitablemethod of sterilization, whether presently known or later developed, canbe employed.

Accordingly, certain methods comprise sterilizing, either terminally orsub-terminally, any of the embodiments of the system 100 or any of thecomponents or subsystems thereof disclosed herein, including but notlimited to any of the embodiments of the sheath 110 or light deliverydevice 150 disclosed herein. Any suitable method of sterilization,whether presently known or later developed, can be employed. Forexample, the method can comprise sterilizing any of the above-listedapparatus with an effective dose of a sterilant such as cyclodextrin(Cidex(™)), ethylene oxide (EtO), steam, hydrogen peroxide vapor,electron beam (E-beam), gamma irradiation, x-rays, or any combination ofthese sterilants.

The sterilization methods can be performed on the apparatus in questionwhile the apparatus is partially or completely assembled (or partiallyor completely disassembled); thus, the methods can further comprisepartially or completely assembling (or partially or completelydisassembling) the apparatus before applying a dose of the selectedsterilant(s). The sterilization methods can also optionally compriseapplying one or more biological or chemical indicators to the apparatusbefore exposing the apparatus to the sterilant(s), and assessingmortality or reaction state of the indicator(s) after exposure. As afurther option, the sterilization methods can involve monitoringrelevant parameters in a sterilization chamber containing the apparatus,such as sterilant concentration, relative humidity, pressure, and/orapparatus temperature.

In view of the foregoing discussion of methods of sterilization, furtherembodiments comprise sterile apparatus. Sterile apparatus can compriseany of the apparatus disclosed herein that are intended for insertioninto (or other contact with) the patient or that are intended for use ator near the surgical field during treatment of a patient. Morespecifically, any one or combination of the following can be provided asa sterile apparatus: any of the embodiments of the system 100 or any ofthe components or subsystems thereof disclosed herein, including but notlimited to any of the embodiments of the sheath 110 or light deliverydevice 150 disclosed herein.

While certain embodiments have been described, these embodiments havebeen presented by way of example only, and are not intended to limit thescope of the disclosure or of the patent protection sought in connectionwith this specification. Indeed, the novel methods and systems describedherein may be embodied in a variety of other forms; furthermore, variousomissions, substitutions and changes in the form of the methods andsystems described herein may be made without departing from the spiritof the disclosure.

1. Apparatus for treating a hollow anatomical structure, the apparatuscomprising: a sheath, the sheath having an elongate shaft defining aninternal lumen, the shaft having a sidewall, a proximal portion, and adistal portion, the sidewall being more transmissive of therapeuticlight energy in the distal portion than in the proximal portion, thedistal portion forming a distal tip of the shaft and having adistal-facing opening at the distal tip; an optical fiber disposedwithin and movable along the lumen, the optical fiber having a fiber tiplocated in the distal portion of the shaft at a firing position which is2-20 mm proximal of the distal tip of the shaft; and a light propagationpath which extends distally from the fiber tip and through thedistal-facing opening.
 2. The apparatus according to claim 1, whereinthe firing position is a static firing position relative to sheath. 3.The apparatus according to claim 1, wherein the sidewall is made from afirst material in the proximal portion and from a second material in thedistal portion, the second material being more transmissive oftherapeutic light than the first material.
 4. The apparatus according toclaim 3, wherein the second material is transmissive of wavelengths oflight from 800 to 1500 nm.
 5. The apparatus according to claim 1,wherein the optical fiber is insertable into the hollow anatomicalstructure separately from the sheath.
 6. The apparatus according toclaim 1, wherein the shaft is sized for insertion into a vein.
 7. Theapparatus according to claim 1 further comprising a liquid flowadvancing distally along the shaft lumen and contacting the fiber tip.8. The apparatus according to claim 7 further comprising a liquid sourcein fluid communication with the shaft lumen, the liquid sourceconfigured to provide the liquid flow at a fixed and predeterminedliquid flow rate.
 9. The apparatus according to claim 8, wherein theliquid flow rate is 5-60 cc/hr.
 10. The apparatus according to claim 8,wherein the liquid source comprises a saline bag fluidly coupled to theshaft lumen through a flow regulator.
 11. The apparatus according toclaim 8, wherein the liquid source comprises a liquid reservoir, aliquid flow path from the reservoir to the shaft lumen, and a flowrestriction comprising an orifice of a fixed size positioned in the flowpath, the orifice size being smaller than that of the rest of the liquidflow path.
 12. The apparatus according to claim 1 further comprising aposition limiter configured to limit the position of the fiber tiprelative to the distal tip of the shaft at the firing position.
 13. Theapparatus according to claim 12, wherein the position limiter comprisesa stop which comprises cooperating structures of the optical fiber andthe shaft that are configured to prevent the insertion of the fiber tipwithin the lumen beyond the firing position.
 14. A method of treating ahollow anatomical structure, the method comprising: inserting a sheathwith a distal end into the hollow anatomical structure; inserting anoptical fiber into the sheath; positioning a tip of the optical fiber ata firing position anywhere from 2-20 mm proximal of the distal end;emitting light energy from the fiber tip while the tip is disposed inthe sheath proximal of the distal end; and withdrawing the sheath andoptical fiber along the hollow anatomical structure while emitting thelight energy.
 15. The method according to claim 14 further comprisingmaintaining the position of the fiber tip in the firing position duringthe emitting and the withdrawing.
 16. The method according to claim 14,wherein the emitting comprises emitting light energy through a sidewallof the sheath.
 17. The method according to claim 14, wherein theemitting comprises emitting light energy through a distal portion of asidewall of the sheath that is more transmissive of light energy than isa proximal portion of the sidewall.
 18. The method according to claim 14further comprising establishing a liquid flow proceeding distallythrough the sheath and past the tip of the optical fiber.
 19. The methodaccording to claim 18, wherein the establishing further comprisesproviding a predetermined liquid flow rate.
 20. The method according toclaim 19, wherein the predetermined flow rate is fixed.
 21. The methodaccording to claim 19, wherein the predetermined liquid flow rate isprovided at 5-60 cc/hour.
 22. The method according to claim 14, whereinthe emitting comprises emitting light energy distally from the fibertip.
 23. The method according to claim 22 wherein the emitting lightenergy distally comprises emitting light energy through a distal-facingopening formed in the distal end of the sheath.
 24. The method accordingto claim 14, wherein the emitting comprises emitting light energy into awall of the hollow anatomical structure.
 25. An apparatus for treating ablood vessel, the apparatus comprising: a sheath defining an inner lumenand having a proximal portion and a distal portion, the sheathconfigured for insertion into the blood vessel; an optical fiberpositioned in the lumen and having a distal tip positioned in the distalportion; a liquid flow advancing distally along the lumen and contactingthe distal tip; and a liquid source in fluid communication with theinner lumen, the liquid source configured to provide the liquid flow ata predetermined liquid flow rate of 5-60 cc/hour.
 26. The apparatusaccording to claim 25 wherein the predetermined liquid flow rate isfixed.
 27. The apparatus according to claim 25, wherein the proximalportion is formed from a first material and the distal portion is formedfrom a second material that is more transmissive of light energy thanthe first material.
 28. The apparatus according to claim 27, wherein theproximal portion and the distal portion have approximately the sameouter diameter.
 29. The apparatus according to claim 25 furthercomprising a flow path from the liquid source to the sheath, the flowpath having a flow passage of a predetermined size that restricts theliquid flow to provide the predetermined liquid flow rate.
 30. Theapparatus according to claim 29, wherein at least a portion of the flowpassage is smaller than the remainder of the flow path from the liquidsource to the sheath.
 31. The apparatus according to claim 30, whereinthe flow passage comprises a channel having a fixed size.
 32. Theapparatus according to claim 25, wherein the liquid source isnon-motorized.
 33. The apparatus according to claim 32, wherein theliquid source comprises a liquid reservoir, and the flow of liquid fromthe liquid reservoir is driven by at least one of gravity andcompression of the liquid reservoir.
 34. The apparatus according toclaim 33, wherein the liquid reservoir comprises a saline bag fluidlycoupled to the inner lumen through a flow regulator.
 35. The apparatusaccording to claim 25, wherein the optical fiber is moveable withrespect to the sheath.
 36. The apparatus according to claim 25, whereinthe distal sheath portion forms a distal tip of the sheath and has adistal-facing opening at the distal tip of the sheath, and the liquidflow passes through the distal-facing opening.
 37. The apparatusaccording to claim 36, wherein the distal tip of the optical fiber andthe sheath define a light propagation path which extends distally fromthe distal tip of the optical fiber and through the distal-facingopening.
 38. A method of treating a hollow anatomical structure, themethod comprising: positioning a treatment system in the hollowanatomical structure, the treatment system comprising a sheath having alumen and an optical fiber with a distal tip located in the lumen;establishing a liquid flow at a liquid flow rate of 5-60 cc/hourproceeding distally through the lumen and past the distal tip; emittinglight energy from the optical fiber, thereby causing heating of a wallof the hollow anatomical structure, while the distal tip is located inthe lumen and the liquid flow is present; and withdrawing the treatmentsystem along the hollow anatomical structure while emitting the lightenergy.
 39. The method according to claim 38, wherein the establishingfurther comprises providing the liquid flow at predetermined liquid flowrate.
 40. The method according to claim 39, wherein the predeterminedliquid flow rate is fixed.
 41. The method according to claim 40, whereinthe providing further comprises restricting the liquid flow from aliquid reservoir to the sheath lumen to provide the fixed andpredetermined liquid flow rate.
 42. The method according to claim 41,wherein the restricting further comprises flowing liquid through asmaller diameter portion of a flow passage coupling the liquid reservoirto the sheath lumen.
 43. The method according to claim 41, wherein therestricting further comprises flowing liquid through a channel having afixed size.
 44. The method according to claim 38, wherein theestablishing further comprises providing the liquid flow rate from anon-motorized liquid source.
 45. The method according to claim 38further comprising maintaining the position of the distal fiber tiprelative to the distal end of the sheath during the emitting and thewithdrawing.
 46. The method according to claim 38, wherein the emittingcomprises emitting light energy through a sidewall of the sheath. 47.The method according to claim 38, wherein the emitting comprisesemitting light energy distally from the distal tip.
 48. The methodaccording to claim 47 wherein the emitting comprises emitting lightenergy through a distal-facing opening formed in a distal portion of thesheath.
 49. The method according to claim 38, wherein the emittingcomprises emitting light energy into a wall of the hollow anatomicalstructure.
 50. The method according to claim 38, wherein the emittingcomprises emitting light energy radially from the distal tip.